The overheating could be the thermostat for me too. The oil consuption could be a "bible" of troubles... Start checking the spark plugs to see where is the problem. Maybe could be a valve seal (or rings), or a simple oil leak. If seals or rings, you gonna find some oil on exhaust, for sure (put a finger inside the exhaust to see). Check the upper gaskets too... who knows.
Good luck,
Chris