If you are getting an A-90, look at putting either the VE-RD1 or VE-GSPro into it. This increases its capabilities substantially.
The JV-2080 is quite a bit different than the XP-50, so don't judge it on the XP-50's capabilities. 2x the Expansion (8 vs 4), 3x the EFX (3 vs 1), larger LCD with a great graphical UI.
I'm using an A-70/VE-RD1 and JV-2080/Exp as my main synths (along with a few JV-80 Engine modules), and they are top-notch.