I think that it is almost impossible to have a genuine"Ultimate amp", I always have this problem, I am always adding, chopping, selling, dealing equipment just to satisfy my tonal desires!!! It drives you mad!! Infact I was at the same level with My DSL and V-twin, because I was hearing all these sounds and thinking, Time for a swap??? But you just cant win.
You have got a really cool set-up that has a fair bit of versatility, I think that next thing has to be a second amp, expensive i know but where will you quest stop otherwise!!!