I use HM2 and Leakbuster for fullest coverage. I'm looking to make sure all my stats are in the optimal ranges for TAG play..
I assume as you are looking to turn Pro you know the stat ranges you are looking for. If you're not sure then I'd thoroughly recommend Leakbuster it is the ultimate leak finding tool. It will analyse 6 max and or full ring. Not sure about HU.
I start my reviews with pre flop opening hand selection by position. Excellent preflop play makes the whole game simpler and avoids getting you into too many marginal spots.
I pay particular attention to what I'm doing preflop from the blinds. If you can minimise leaks from the blinds and reduce your losses to less than -15bb/100 in the SB and less than -30bb/100 from the BB then you are doing great. Mastering playing oop from the blinds and mastering playing the button are two massive keys. We lose most from the blinds and win most from the button so do well in these areas and you should do well overall, so review here is important.
You may want to review common leaks, things like; cold calling especially oop, calling 3bets, especially with small pairs, calling raises with marginal holdings post flop, triple barrelling, check calling all 3 streets, 3betting versus flatting small pairs from the blinds.
You can filter HM2 for just about anything but Leakbuster does it all for you tbh.
There are several videos online about Leakbuster by its creator John Anhalt. In fact he has a blog here on cardschat and he posted a video about how to review properly about 8-12 months ago.