Would it be good to move things around? Sure. If you can convert to LMT, then go for it.

However, you could be setting yourself up to be the fall guy. If there are any performance problems after the move, all fingers will be pointing at you because you futzed th the tables and indexes. Personally, I would do it gradually:

1. Move everything to RAID 5 on the SAN.
2. The next weekend, move 1/3 of your tables and indexes to LMT's (system managed where appropriate).
3. repeat 2 the next weekend
4. repeat 2 the next weekend

Also, measure your I/O performance before and after each step. This way you can prove/disprove improvements.