Overheating, terrible gas mileage and intermittent no start

Please help. All advice is welcomed.
Bought this car with a blown head gasket about a year ago. Long story short the block threads were stripped from previous owner so I replaced it with a new engine. Ran great at which point I replaced timing belt waterpump and thermostat. Gradually the gas mileage started deteriorating, to where now my wife gets sixty miles to a full tank, with no hesitation at acceleration at all short term fuel trim is at positive ten and I also noticed an overheating at scan tool, but not cluster gauge. Before it would reach 203 degrees. Now it going to 208 degrees and sometimes 214 degrees, when fans turn on it brings it down to 196 degrees. I re bled coolant and checked timing and still is on point. See some random very tiny bubbles at radiator neck but not constant. Am I having a head gasket failure? If it was a head gasket would not the temperature keep rising? Are all these symptoms related? I know ignition timing can also cause overheating and mine is a bit advanced I think. Where can I start to diagnose all of this in your experience.