Integrated tube amp vs Tube amp?

I suppose it depends on the particular amps in question, but since you have a tube preamp I'd be inclined to lean toward a straight tube amp.

What is your budget?

There are a lot of options…

Tube pre with SS amp is a champ!!!

Integrated amps are usually purchased in order to save space or compromise in some fashion. If you like the very distinctive sound of McIntosh, then definitely get a tube amp. Tube amps have a real musicality and realism hard to achieve with solid state.

I have a McIntosh C2700 with a MC275. The music the pours from my speakers is so easy and effortless. It's like liquid gold. I never ever get listening fatigue with this combination. I did listen to a C2700 with a MC462 at the dealer. Fantastic combination if you want a stronger or bass presence with more authority. 
The Tube pre-amp / SS amp combination absolutely has a different sound characteristic than all tube. I went with the tube amp because I just personally favored it over the two. I really enjoy that lush warm blanket of sound it creates.  

Only one word of caution. Be wary of the tube rolling rabbit hole if you go all tubes. It is real and it goes on forever.....