Hi, what You did is actually modeling a quite long, but in the beginning not overly high baffle. That's quite a different thing compared to a raised floor. Baffle, floor, sidewalls, transitions, rails, chamber design - and their relation to each other will all have impact on sound and playability. Changing one ore more parts may give great or unwanted results - You never know before, if You're not a mouthpiece expert. Simply raising or extending a baffle might be not enough to really succeed in the best possible way. But maybe You're lucky and found a nice spot with Your handmade baffle extension. But I think really important is, that You're not completely happy with Your mouthpiece in original condition.
I think there are three options for You:
1) You play that modified mouthpiece as it is and hopefully the baffle extension will stay for a while
2) You'll find a mouthpiece master, who will make your modified mouthpiece perfect with e.g. epoxy like Morgan Fry in GB (who can make You an awesome custom mouthpiece) or Phil Engleman, who already replied.
3) You'll try some different designs, which might fit Your imagination of sound und playability better compared to Your current mouthpiece (what will be a lot of fun, but can get expensive, time-consuming and confusing ;-)). The models You already mentioned are far away from a "classic" concept (Jumbo Java cutting sound, Berg Larsen is a completely different thing.
Maybe You'll try some "Link" type models - in addition to some great Early Babbitt (which might be expensive) HR and metal pieces and really expensive Florida ones there are some contemporary made mouthpieces in that area of design - Morgan Fry (e.g. Vintage and Super Vintage, Jazz+), Philtone, Johannes Gerber, Matt Marantz, Navarro Bop Boy, Aaron Drake New York Jazz and of course some others...