Phantom the glassy water/high density altitude full scale technique you are talking about I have no doubt will aid a struggling ship get off but is a rather tricky technique in RC part of the problem is most takeoffs that may be marginal are done left to right or vice versa due to the need to visually see the floats water line angle, which is fine but now the needed cross control technique becomes difficult to judge. If you takeoff straight out from the beach the cross controling becomes easier but telling the waterline angle is difficult as the airplane gets smaller and smaller. There is one fun thing that is great fun and an attention getter that is actually easy to do if the float installation is decent. That is a circular single float touch and go.
It is not cross controlled like a straight single float t/o but mearly flying a big circle pattern holding a steady coordinated bank and just powering down and holding some power to a contact point in front of you just as the inside step makes contact apply slightly more aileron and you will be in stable single float step contact with the aircraft still flying in a big circle and at any point if the water is smooth just apply full power and your fully airborne agine in the turn. Sounds complicated but much easier than straight single float flight and will make you the hero of the float fly.
Normal takeoffs are as you know are just like full scale but in a way easier because you can watch the floats water line as you climb onto the step and rotate, you can even see if you start to drag your heels. Just with as with full scale with a heavy wingloaded airplane landings need to carry a little power and a lightly loaded ship can land power off fine. Of course full elevator on the water. RC's can be sailed just like full scale with idle power or dead stick buy control surface positioning in the wind just like full scale.
Float RC is not hard and is extremely satisfying once you get over the fear. Now possibly the most euphoric experiance you can have in RC is night float flight, it is magical. Probably my favorite activity in RC athough I only have the opportunity to do it at the London Bridge float fly each year. The airplane in my Avitar will be my lastest night float flyer at this years event in November.
Happy sailing
John
Almost forgot, Forget the wood props and yes prop clearance will decide how long you can use and with your type airplane longer and flatter is always better.