TL494 NO Good!
It's the UCC35702 and will work down to 10V so fine on a draining battery.
you wont get low mod % with a TL494.
YES! it's a DC to DC to float the supply for High side drive, could be done much easier with low side drive but don't fancy a floating RF earth!
This style of circuit is the ONLY one to use, done bother with the linear one, it's class A and ONLY 20% eff, PWM is 90%+
Having a PCB negates any complication issues, if you can solder you can build it!
2 chips, a FET & a diode, why use anything else??
OK have added my orig 2 FET design with audio LPF, will pass 1/2 KW, YES 500W, crazy!