Couple things, all of which depend on how high you are shooting for.
1. First off, are you SURE you get a 1.5mos of dedicated time? Make sure that will actually be dedicated time and not time spent doing useless DO school BS. If you actually get 6wks off, congrats man.
Yup just around 6 wks
2. Related to that, do not assume the months leading to dedicated will be light. Just about everyone in our school kept saying, "Okay... that was more annoying than I wanted, but this next month will be easy... right?"
From what I've heard, the 6 wks leading up to it are easier (let's say at least ~4 hrs/day for boards)
3. Are you planning to take Step 1? If so, how high are you shooting?
Idk...if I am 100% sure I can get at least a 220
4. Do not study anything OMM related until dedicated, and even that might be too early. Savarese is an absolute dog-crap book that was outclassed by some of my classmates half-ass putting together their own studyguides. Savarese does not even exist in the same realm as UFAPS in terms of quality.
5. I am indeed one of those people who took forever to review a single Uworld block, but even by dedicated I was going through two blocks a day. Just make sure you don't spend too much time on each question and keep moving.
6. As for your last question, I did one pass of Uworld and did above average on COMLEX and below average on Step. I spent too much time making flashcards/notes instead of just reviewing or retaking questions. As NecFasc said, the more ?s the merrier.
PS, 7. Seriously, screw Savarese.