I would not be terrified of 3.5" of scrub radius, it'd be better to have a bit less, but this in itself isn't horrible. What doesn't look so good to me from these numbers is the roll center lateral migration. I did note before that I felt like having it absolutely minimized is neat, but there is probably more to the bigger picture, which might have implied "let it do what it wants." Sorry if that was the case, I "still" like to keep it quiet in bump/roll, so seeing it move 10" + at 1"/2 degrees would concern me. A lot. Looks like you can play with the upper arm angle a bit, it'll raise the static roll center case (hint-hint, wink-wink...), but it might make things happier overall. Again, BIG disclaimer, this is my "opinion," your mileage may vary, and if it doesn't do what you expect it to, don't blame me!!!!
Just another note on roll center height. There is, without any doubt a physical importance to keeping it low, as Tad pointed out: jacking. But here again, be careful about getting too deep into the "rules" that the text material states, or rather don't be scared about it. I say this because a lot of the time, the cars they are referring to are open wheel cars that are really light, and have incredibly low gravity centers. We should be so lucky with our cars, but we're not. My personal rule is to get concerned if the static roll center height is greater than 4" for the front, if everything else looks super happy, then I am basically cool with it. If not, then I work to address this (i.e. consider lowering FRCH) at the same time as slaying the other dragon(s).
All that said, I'd bet that your sheet represents an improvement on a LARGE number of existing aftermarket suspension setups currently on the market, I can't confirm that because unless you have all of the numbers it's impossible to make specific claims, but just understanding the rules a bit, well... You can look at a setup after a while, and make darned good educated guess at whether it has issues or not. Lots of them do. Lots.
One more point, you noted the circle track type spindles. They can be used with tremendous success, and all of the ones that I have seen (use the steel ones, not aluminum for the street, please) are really tough. Biggest downfall that can be a deal breaker is the hubs, they generally run a 5x5 bolt pattern with 5/8" studs, and scrub radius is not of primary importance to them seemingly. It's really, really hard to find street wheels that you can run with those bolts. Bummer too, the stuff is cheap!
Have fun!
M
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