Welcome to Amiga.org.au...!
Soz got carried away there; Amiga.org.
Ive got a 2000 too. If the A2000 battery is original it probably is best to remove it. It will be NiCad.
As to what you might want to do additionally, one option is getting a Buddah IDE Card.
And the best way to get more RAM is the 32Bit variety on an Accelerator.
It depends on what you want to use the beasty for.
BTW: I think I've got a spare 1GB Quantum SCSI around the place for your A2091.
I'm up in sunny Melbourne.
PS. You can ignore Franko, he obviously doesnt realise that as most of the world's land mass is in the northern hemisphere that means it must be the lower half of the world.
Franko, have a read of this and you'll realise how brainwashed you've been.
http://flourish.org/upsidedownmap/