yes, i rode my friends custom titanium aitken and it was ridiculous. i tried airing a quarter and landed to flat. keep it in the low 20s and ull be good (i.e. 23lbs is perfect)
for street the capital would be better as the smaller wheels allow for easy tricks ( 180's etc...) also the 24 inch frame will have shorter chainstays so it will be easier to manuel and stuff like that.
The capital 2 has 110mm spacing between the dropouts, so you will need to use a bmx hub. But doesn't really matter because they are lighter and you don't seem to be wanting to run a disk brake.