not an expert, but I'm sure dents get filled in with brass and sanded smooth, rather than pulled out. you'd then need to add paint cost as well, unless you clerverly used stickers to disguise.
Don't think you can suck out bike tubes like you can car panels.
A frame painter would fill it as part of a spray, but I wouldn't worry about a dent like that. It shouldn't lower the value much if you sell it, and a home-made fill and cover would probably be worse in that regard.
