That is a great idea. The new direct drive trainers (Wahoo Kickr / Tacx Neo / etc) mitigate the wheel slip problem completely - my Neo can handle power outputs of up to 2200W, which is more than enough (by about a factor of 2) for me. That plus an aluminium bike to put on it (carbon bikes don't much like that level of power when they're anchored as on a turbo) seems to work well, but the issue with sprint bars remains and it's a much more expensive solution than yours is.