All my ideas wouldn't be financially sound. Basically, they all surround my perception of FM radio being mainly current hits (whether its Top 40 or Hot AC), country, and talk (political or sports). So, I'd eliminate most of the repeats.
Bring in more experimental formats. Have a true Rap station like the old WBOT and WILD. Bring back Radio Mojo and put it on a main frequency. Move the Red Sox over to The Sports Hub and flip WEEI to a true FM Spanish format. Heck, its city of license is Lawrence.
Keep Toucher & Rich in the morning, and put Dale Arnald and whoever in the afternoon. I hate WEEI's morning show and WBZ-FM's afternoon show. Bring WBZ-AM to FM. Have more experimental Alternative on WBOS that would be similar to Indie 617. Flip either Mix or Amp to a modern version of plastic hits (90s and 2000s).
In essence, keep Magic (even though I don't listen), WZLX, WBOzd either Kiss or Amp, either The Bull or WKLB, either WEEI or WBZ-FM, and either Hot 96.9 or Jamin. Then flip the rest to something unique. Again, the reason that many stations program with the current formats is because those formats is what brings in money.