It All Depends on What You Plan to do with It
It's almost like my other mantra of "It All Depends on How It's Wired!" Really.
The WM catalog has a very good writeup in the Advisor section on dinghies, and explains, patiently, that the selection of a dinghy, at ANY time in a skipper's & crew's lifetime, is based on how they plan to use the dinghy.
If you anchor out a lot, but ONLY are 300 yards off the beach, then you most likely don't need (not want, I say, but need

) a 15HP 12 foot RIB. A smaller inflatable for the suggested Walker Bay - type solid dinghy of ANY kind, would suffice.
If, however, you need to use the dinghy for longer jaunts and/or have areas where you can, and like to, go fast, then you'll need a different platform or else you'll be disappointed in your purchase.'
Two examples: Same skipper, different boats, same anchorage:
Example 1: Skipper, Me! Boats: Catalina 25 with a 8'-4" West Marine older 1989 with what I called my "egg beater" Johnson 1.2 HP only forward gear 2 stroke engine. Anchorage: California Delta, Three River Reach, which is about a mile from the closest ice and beer store.
It took an hour to motor there in the dinghy with my then 12 year old daughter. We had fun, were in no hurry and the dinghy worked just fine for us because we always kept a small 1 or 1 1/2 gallon jug of premix fuel in the dinghy. That was essentially the furthest we ever had to "run" the dinghy to get somewhere, all the rest were actually row-able boat to shore excursions.
Example 2: same skipper. Boats: Catalina 34 with a Zodiac Cadet Fast Roller Hi pressure Air Floor 10'-2" with a 9.9 HP Evinrude pre-owned 2 stroke. Same anchorage, get to the same place in 10 minutes! Ended up going further up the Delta to Lost Slough which is about 2 to 3 miles to the stores. Because of speed limits in much of the area, couldn't go fast except for less than a half mile of the whole trip anyway to do laundry, buy supplies and tour around. But we bought the biggest, fastest "rig" we could because we knew we would be in places that would allow us to get out and stretch the legs of the bigger dinghy.
Sometimes I wish I'd kept the older 1.2 HP engine, 'cuz I could manhandle it with one hand from the boat to the dinghy. With the 9.9 HP I use our Garhauer dinghy motor lift, which is a great piece of equipment. Shoulda had both engines, to give me a choice, but the dinghy is great, been going on 10 years and it's in great shape, but no FL sun and we keep it delfated and either down below or home when not in use.
I notice you had an RIB, so if you liked or disliked it, what were
your reasons? Good luck on your choice of replacement.