RE: '94 940 w/ '88 240GL motor. Fresh tranny fluid/filter 20k ago. No sign of tranny damage upon fluid change (v. few metal shavings on magnet).

Hello,
First off, I'm new to AC... I've just gotten it working over the past few months for the first time.

A few questions:
I've noticed that my car doesn't really want to shift until over 3500 RPMs. This is annoying as a lot of the driving I do is around 30mph and flat so I'd like to cruise at 2200rpms or that area but to accomplish that I either need to speed up to around 35mph and let off the gas to get it to shift or try lifting off the gas a few times around 30mph to get it to shift. Is there anyway to get this thing to shift more readily? Additionally, there seems to be some slight hesitation around 3200rpms, shortly after I hit what seems to be the powerband around 2800rpms.

This doesn't really seem to be an issue when the A/C is off, however. It seems that the A/C is robbing the engine of a lot of power... like 20+%. Is this normal? Anything to do about that?

Would putting in synthetic tranny fluid help this? Is there anything on the computer that could be altered to allow for an earlier shift? Any other thoughts?

I should have put in a turbo...

Thanks!