What amp & preamp to go with JM Lab ?

You mention you want a less analytical sound? Have you considered a change of cable rather than amp and pre-amp.
If you want to try a better amp pre-amp combo, when I was auditioning the 926 and 936 before I bought my speakers, I listened in two stores onboth Parasound and McIntosh and I felt the McIntosh controlled the bass better and offered a more accurate high.

I would suggest a push-pull tube amp for the Electras; there are plenty of models out there that should work well.

I am using an AI modulus 3A and Plinius SA-50 (which is Class A SS) with my Electra 906. The result is very satisfying music to my ears - never analytical. But cables are also very important. What cables are you using? The electra range of JMLab can easily sound analytical if one is not careful with the supporting cast.