First about the stat points per level up: I strongly have the impression that those figures aren't exactly right. You'll get the right impression if you average over 10 levels (say compare level 1 and 11).
Strongly disagree with Physical Strength being kept at one at most; the height the finishing hit launches increases per level. So its comboing ability increases along with it. Though it tends to throw your enemy too high when the level's really high, I'd say I'd recommend anywhere between 4 and 6.
Hammer Scratch is 10 (ten!) hits, making it a very worthwhile skill. Okay, you can't always get all 10 hits in, but more often than not, I can get at least 8 hits in. Plus, at high level, it transforms into a very long range skill (135!). Max it!
Vehement Transformation's power grows 10% per level, on average. So yea, like you said, definitely worth leveling.
For the rest, a very solid guide! Keep the good work up!