In regards to the beach, Coca LaPalm offers some great specials and is quite kid friendly...as well as a great location. For the cliff, I recommend Catcha Falling Star Gardens. For the price...it can't be beat. No, you are not on the water but if you get the front upstairs room...you can see the water! It is right across from LTU which is a great place to eat and a view that is one of the best. It is well enclosed for kids and the pool is truly lovely.
Ricks is not far away and the entrance to the sea is quite easy there. If you go in the early afternoon, it is not crowded and you could snorkel, swim and then grab a drink or a snack as your way of re-paying them for the courtesy. You can also enter the sea at LTU, but it is a bit more difficult maneuvering the long ladder there.
Obviously, there are many places to choose from....but as most of us who do travel there...$$$$ IS an issue. It can be done reasonably with some research. Whatever you choose...have a great time!