Dashboards are always fresh calculated.

Compare the performance in .NET  to  IE.  It should be rather close to each other being based on similar technology.

If there is a significant difference then you dig at  .NET end (buffers, ...)

If Chrome is significant faster then IE it's most likely the faster JS engine in Chrome.

Next you could look into global buffers of Caché and concurrent use of the Caché instance.
And (rarely) the complexity of your dashboard
 

The parameters are defined all over here:

 Searching for 'SERVICEINPUTCLASS' in 'Ens*.cls' (whole words,case sensitive)
Ens.Enterprise.MsgBank.BankTCPAdapter.cls(SERVICEINPUTCLASS): Parameter SERVICEINPUTCLASS 
Ens.InboundAdapter.cls(SERVICEINPUTCLASS): Parameter SERVICEINPUTCLASS 
EnsLib.DICOM.Adapter.TCP.cls(SERVICEINPUTCLASS): Parameter SERVICEINPUTCLASS 
EnsLib.EMail.InboundAdapter.cls(SERVICEINPUTCLASS): Parameter SERVICEINPUTCLASS 
EnsLib.File.InboundAdapter.cls(SERVICEINPUTCLASS): Parameter SERVICEINPUTCLASS 
EnsLib.HTTP.InboundAdapter.cls(SERVICEINPUTCLASS): Parameter SERVICEINPUTCLASS 
EnsLib.Pipe.InboundAdapter.cls(SERVICEINPUTCLASS): Parameter SERVICEINPUTCLASS 
EnsLib.SQL.InboundAdapter.cls(SERVICEINPUTCLASS): Parameter SERVICEINPUTCLASS 
EnsLib.TCP.CountedInboundAdapter.cls(SERVICEINPUTCLASS): Parameter SERVICEINPUTCLASS 
EnsLib.TCP.DuplexAdapter.cls(SERVICEINPUTCLASS): Parameter SERVICEINPUTCLASS 
EnsLib.TCP.FramedInboundAdapter.cls(SERVICEINPUTCLASS): Parameter SERVICEINPUTCLASS 
EnsLib.TCP.TextLineInboundAdapter.cls(SERVICEINPUTCLASS): Parameter SERVICEINPUTCLASS 
EnsLib.UDP.InboundAdapter.cls(SERVICEINPUTCLASS): Parameter SERVICEINPUTCLASS 
Found 13 occurrence/s in 13 file/s.

 Searching for 'SERVICEOUTPUTCLASS' in 'Ens*.cls' (whole words,case sensitive)
Ens.Enterprise.MsgBank.BankTCPAdapter.cls(SERVICEOUTPUTCLASS): Parameter SERVICEOUTPUTCLASS 
Ens.InboundAdapter.cls(SERVICEOUTPUTCLASS): Parameter SERVICEOUTPUTCLASS 
EnsLib.DICOM.Adapter.TCP.cls(SERVICEOUTPUTCLASS): Parameter SERVICEOUTPUTCLASS 
EnsLib.HTTP.InboundAdapter.cls(SERVICEOUTPUTCLASS): Parameter SERVICEOUTPUTCLASS 
EnsLib.TCP.CountedInboundAdapter.cls(SERVICEOUTPUTCLASS): Parameter SERVICEOUTPUTCLASS 
EnsLib.TCP.FramedInboundAdapter.cls(SERVICEOUTPUTCLASS): Parameter SERVICEOUTPUTCLASS 
EnsLib.TCP.TextLineInboundAdapter.cls(SERVICEOUTPUTCLASS): Parameter SERVICEOUTPUTCLASS 
Found 7 occurrence/s in 7 file/s.

But there is no case where it is used.

Looks like "reserved for future use "

The diagramm shows to me  2 object REFERENCES (oref)
oref consists of a  (local) integer@Classname  and points to an object.
in your case both are of type %Collection.ListOfObj 
by the reference you can't tell that this is the same.
any ##class(%Collection.ListOfObj).%New() will create a new oref
in your case I see a count of 1 and then a count of 2 
you should look what happens in or after (19)  and in or after (29)
looks to me like a fresh return value

set CountRow=pObject.IssuesList.GetAt(i).Count()

you assume pObject.IssuesList.GetAt(i) gives back a %Collection Object (Iist, Array, ..)
Before applying method .Count() you should check if this assumption is true.

your previous description with ASSIGN / APPEND wasn't that convincing that you always have the object you expect.

ref: "out of the scope of ENSEMBLE to an external class" 
you should save anything that you want to keep over that call in one/multiple property of %context Object.


 

to work down a collection of varying number of elements I'd use this kind of loop
in this case it's a double loop

For res=1:1:callresponse.result.Count() {
  Continue:'$IsObject(callresponse.result.GetAt(res)
  For err=1:1:callresponse.result.GetAt(res).Count() {
    Continue:'$IsObject(callresponse.result.GetAt(res).errors.GetAt(err)
    Set context.ErrorMessage= callresponse.result.GetAt(res).errors.GetAt(err).message
    - - - -
    }
 }

This is the paranoic version!
If you trust ENSEMBLE you may skip the check for $IsObject()

HTH

online docs don't give a direct hint.

so my shot from the hip: 
selection expression - $select(), $case()  where you get a value based  on a condition
data expression - anything that sets, modifies, composes data.

this is  a quite academic view since  data expressions may contain selection expressions
and selection expressions may contain data expressions.
both variants and any mix of it  are quite common in COS 

HTH

I did a short test fiddling arouned ^Samples.PersonI

SAMPLES>Do $SYSTEM.OBJ.ValidateIndices("Sample.Person","",1,2)                   
 
Checking index integrity for class 'Sample.Person'
Begin time:  08/17/2017 21:41:25
 
Verifying data from data map 'IDKEY' is indexed correctly...
Index 'NameIDX', entry ^Sample.PersonI("NameIDX"," CHANG,QUIGLEY H.",39), has differences between master map data and index map data.  Corrected
Index 'NameIDX', entry ^Sample.PersonI("NameIDX"," CHANG,DAN L.",40) missing.  Corrected
Index 'NameIDX', entry ^Sample.PersonI("NameIDX"," CHADWICK,OLGA E.",43) missing.  Corrected
Index 'NameIDX', entry ^Sample.PersonI("NameIDX"," CANNON,BARBARA W.",81) missing.  Corrected
Data Map evaluation complete, 200 rows checked, 4 errors found, elapsed time: .004733 seconds
 
Verifying data from index map "$Person" is correct...
Index map "$Person" evaluation complete, 0 errors, elapsed time: .000691 seconds
 
Verifying data from index map NameIDX is correct...
Index 'NameIDX', entry ^Sample.PersonI("NameIDX"," CEMPER,DAN L.",40), data differs for field 'Name' between data and index map.  Corrected
Index map NameIDX evaluation complete, 1 errors, elapsed time: .001331 seconds
 
Verifying data from index map SSNKey is correct...
Index map SSNKey evaluation complete, 0 errors, elapsed time: .001195 seconds
 
Verifying data from index map ZipCode is correct...
Index map ZipCode evaluation complete, 0 errors, elapsed time: .001255 seconds
 
%ValidateIndices is complete, total elapsed time: .012282 seconds
 
SAMPLES>

This looks good so far.

Similar using  Class %System.License. ...  you may reduce the number of allowed connections by USER
This might  be interesting in SaaS situation.

classmethod SetUserLimit(MaxLU As %Integer) as %Integer

$SYSTEM.License.SetUserLimit establishes the maximum number of license units that this Cache instance will consume. This permits a system manager to prevent a Cache instance from consuming all the license units in a MultiServer key shared among multiple Cache instances. The Method returns the former maximum value. In the absence of a call to $SYSTEM.License.SetUserLimit(max) a Cache instance may consume all available license units. 

Requires access to the %Admin Manage resource.

Using  Class %System.License. ...  you may reduce the number of allowed connections by instance

• classmethod SetConnectionLimit(MaxCon As %Integer) as %Integer

$SYSTEM.License.SetConnectionLimit establishes the maximum number of connections permitted per user on this instance. This enables a system administrator to prevent a user from making so many connections to a Cache instance that they consume all available license units. Calling $SYSTEM.License.SetConnectionLimit($SYSTEM.License.MaxConnections()) permits a user to make the maximum connections permitted but prevent transitioning to the license unit per connection state, insuring the user will consume no more than one license unit. A zero argument removes the limit. The failure to obtain a license will be indicated in the normal way. For example, a call to $system.License.Login() will return zero (0) while a failure to log in to a new terminal connection will receive a error. However, these license failures will not be reported in the console log. The method returns the former maximum value. 

The limit applies only to the local instance. If a Cache MultiServer license is shared among several instances it is still possible to exceed $SYSTEM.License.MaxConnections() over all instances. This can be avoided by setting the limit low enough on each instance that the combined connections to all instances will be unlikely to exceed $SYSTEM.License.MaxConnections(). 

$SYSTEM.License.SetConnectionLimit reqires access to the %Admin Manage resource. It is suggested that customers call this API from SYSTEM^%ZSTART.