First way for me please, if the kids are good enough, ala Gabby, they will breakthrough anyway. A few years ago we gave the kids a chance, Whittingham, Davis, gardner, Cahill, Ridgewell etc, they did ok but I didn't find it particularly exciting.
We sold those players for something like £15m which will have heavily subsidised further signings. Not the mention the games those players contributed in.
For me the Youth don't have to "make it", being competent and filling squad positions is fine. It'll provide turnover through sales and crucially means we have to buy less squad fillers meaning that the "buys" can be fewer but of better quality.
Hopefully the marquee signings will be sufficient to convince gabby/young etc that the club is going places and ambitious.