You need to brush up on specs and their meanings to a degree. Looking at your unit's manual it's rated at 80wpc (8 ohms, 20hz-20khz, at .08%THD). I'm not sure where you get the 65wpc spec from. Sure, an all channels driven test will not yield 80wpc but that's largely irrelevant. At any given time in each channel you can get up to 80w, tho. If you double the power you'd gain 3dB spl. Not saying a more powerful amp may not help, it well could. An avr with more flexible bass management (crossovers per channel/speaker can be nice) may be nice, too.
Your speakers largely have those "bi-amping/bi-wiring" terminals due to the competition having them, and your avr as well; in any case your avr is sending the same signal to each. Real bi-amping requires the removal of your passive crossover networks and two amps and an active crossover. Try this on the subject of passive bi-amping as you're doing
https://www.audioholics.com/frequent-questions/the-difference-between-biamping-vs-biwiring
The power supply I'm sure is more capable than only 245W, you might be looking at some sort of consumption spec that's undefined? Many do look at such a spec and misinterpret/extrapolate.
Hard to believe you're only getting 80dB spl but I don't know how far from the speakers you are, either. How far away are you and how did you measure 80dB? Your speakers can do quite well on 25watts, it's not a minimum "needed".