I accept the realities of the industry, but 1500 hours is hardly inexperienced. You're addressing part of the problem, certainly, but although I don't know the statistics I'd imagine 1500-hour FO new-hires outnumber high-time pilots transferring in.
Regardless, the shortage is a whole different animal. In regards to the context of this thread - raising regional pilot pay - I think the best utilitarian solution is to help the greatest number of pilots. Since most only reside at the regionals for several years, squeeze the pay scales towards the middle. Bring the pay up for the 80% of guys aiming to get their time and go to the majors within several years.