Hi
The most important thing I have found with these amps is burning them in.
I got mine and was really eager to play it and was really happy with it, but only gave it a short burn in.
Then I turned it on 1 day and left it on for 3 days straight and what a difference to the tone, best sounding amp I have owned
The next most important choice is speakers.
My cab had Celestion Vintage 30's and now I have Warehouse Guitar Speaker ET-65's which are a clone of Celestion G12-65's and these sound so much better than the V30's with this amp.
I haven't tried EV's yet but they seem to be a very popular choice on this site.
Good luck with your new amp