It'd be nice to know what the actual temperature of the engine is instead of just somewhere between C and H. I think you're on the right track though. Bleed is of the utmost importance. Sometimes it is necessary to drill a hole in the thermostat if it doesn't have a toggle valve or even to leave the housing loose during the initial bleeding.
Hopefully you won't have to do the water pump again for a very long time. It's going to be tough with that adhesive holding the gaskets to the block. I like to use 3M weatherstripping adhesive and put a thin layer on the water pump. I spread it out into a nice, even layer and let it tack up for a few minutes. I then lay the gasket on it, pull it up once (the adhesive will get stringy, not unlike contact cement), and then slap it down once and for all. It will hold it in place and assure that there are no leaks on that side. As long as the block side is perfectly clean you won't have leaks there installing it dry either. The best part is that the next time you have to remove it the gaskets stay (mostly) attached to the water pump you're either chucking or returning as a core and not to the block.