I think you've misunderstood a few of the characters.
I feel like you discredit Double's point, Peacock's assists, Cerebella in general, and overestimated Valentine and Painwheel's dead weights. I think Painwheel should be a bit higher on point, and Fukua should be at the top left as Lord Tier.
First off here's an updated chart:
http://bombch.us/fnz
I edited a bit here and there.
I'm not even tuning in on Fukua until I have experience with her. Me and a couple friends messed around but didn't really do much with here and I haven't been on beta.
Double's point was not discredited, on the contrary I put her towards the middle of the cast. I know she's a very consistent character. She has something for just about every matchup.
Peacock has bombs and MP Bang for assists, maybe Cannonball, as far as I know. Bombs are good but not amazing, comparatively. The chart is subjective by definition, so if you think those assists are much more useful than I do give some reasons.
Cerebella was a tad underestimated, I actually moved her up in both assist power and point power. I stand by Cerebella's point placement unless you can convince me otherwise though, she doesn't have an amazing neutral.
Valentine and Painwheel's assist placement is relative to the absurd power that a lot of the cast has (Peacock's placement too for that matter). They have inferior lockdown, Val's c.mk is gimmicky at best, though I guess Savage Bypass and Pinion Dash have fullscreen value. Painwheel's s.mk is apparently good but I haven't witnessed it firsthand yet. I had forgotten Savage Bypass existed for a second also, so that puts Val on the same level as Painwheel in my opinion.
Painwheel's point value is hard to determine just because she's so hard to play and no one uses her to her full potential. Her placement was partially biased by how hard she can be to play well. Her normals have good range and she can hit confirm well and flight canceling is great, but it's all sluggish and easy to stuff. That's why people utilize her armor, at which point it becomes a total matchup game depending on multihits and the like. I could go on and on but this isn't a Painwheel thread.
tl;dr for being so technical Painwheel is easy to stuff