Randy this is ONLY MY OPINION....
You have a GREAT point...but I (I) think that Merc is taking the known, proven, and reliable 500 EFI power plant; adding reliable horse power and compromising nothing with complimenting technology. The up-charge from the 500EFI to the 525 is no where near what the 575 is compared to the 500EFI.
Randy I know your question/thought is from a racers point of view...and I had the very same question as well, only my thought was to make #6 the drive to use in F2...WAY cheaper over a season than bravos. For the most part EVERYONE that starts the race will finish the race without mechanical complications....AND the added bonus would be all the teams that begin the year can complete the season with very low mechanical complications. Thus, preventing not finishing the season due to financial constraints.
Randy...you did a great job this year not only standing on the podium every race but your over all presence at the races!!! if your racing F1 next year, please let us know if we can help in anyway. if your coming to F2....be sure to always check that drain plug!!!