Best MM?

I will say, I do think I've found the bass I've been missing!

What arm do you use with your 2M?

SME Model 10A turntable. It comes stock with an SME 309 variation tonearm.

All of the best mastering engineers from the golden era of music (60s-80s) preferred MM to MC. 

I’ve also personally compared MC and MM to many real actual master tapes. MC is severely EQed and distorted. MM is practically indistinguishable from tape.

Any of the Soundsmiths in that price range. Very neutral, dynamic SQ. I've had carts from Shure, Sumiko, Clearaudio, Dynavector, Ortofon and a few others in that price range and found the Soundsmith's worked and sounded the best in my system.

I use a JA Michell Gyro SE with the latest Gen Techno Arm and so far the Two cartridges I really love in the $1K range are the Dynavector 20X2L and the CA Maestro Ebony V2. Now these are both completely different in great ways....The Maestro is beautiful and detailed, rich with a heavenly sound that excels with acoustic and vocals...just a gorgeous sound. The Dynavector is much lower output and requires a proper phono stage. The sound is ALIVE and very dynamic in that leading edges and attacks seem to be more there, you can hear the snappy snare drum and feel it too, the 20X2 is very detailed and everything I play sounds different bad or good. So while both of these are great choices it comes down to musical taste and what sound your trying to get from your system. Also, I use a Manley Chinook phono stage so I was able to dial in both these cartridges very well.
Matt M