Re: Super Robot Wars: There's actually three on the GBA that's in english -- the OG games, that you mentioned, that use entirely original characters, and J, which is part of the SRW main series (Read: Megacrossover madness.) and was fantranz'd... sometime last year? *checks* Yeah, 2010.
As for english (SRPG) SRW games go: You've got SRW1, on the gameboy, SRW3, on the SNES, SRW Alpha Gaiden, on the PSX, and then the GBA ones. Of those, only the OG (Original Generation) ones were ever officially translated. The copyright entanglements involved in the SRW series is hilariously complicated -- they're (each and every one of them) basically mega-crossover fanfiction involving upwards a couple dozen giant robot series. The chances of non-OG games ever seeing an official state-side release is basically zero.
Plot wise, each game (at least within the confines of that game) has seemed to be disturbingly self-consistant. Like I said, it's megacrossover fanfiction... that's actually well put together (Protip: That doesn't happen very often.). The fights are also pretty tough if you don't hack up your money to infinite
If you have any love whatsoever of giant robots, SRW is just something you need to do, at least occasionally.