What should i do to my 2006 ford Mustang GT?

I've had my mustang gt for about a year now and i got it with 95k and i've got about 113k miles on it. I'm planning once in the future once the engine dies to either get another 4.6 and just build it up or should i swap it with a 5.0 coyote engine or a shelby gt500 5.4l sc. Thats the future like in about 2 years so i'm saving up. Will it be better to just get another 4.6 and build it or swap it and build that engine. For now its making 280whp on the dyno. Stock only exhaust. What should i do to it for now i'm thinking a cold air intake and headers and an x pipe. Let me know what i should do. I don't like it stock because all the 5.0 owners always just play around with me. So i'm trying to gain some horsepower

Hi best if these engines get overhauled first before they are put init also you will need the engine management system that goes with each engine as this controls how they perform and run.

The factory 4.6 block can hold 700 or a bit more horse power before ti splits down the middle. If something less then that will do you just fine, then a factory block will do the trick. The new 5.0 Coyote is nice, but expensive - Maybe seven grand. How about a pair of Trick Flow two valve heads, some decent cams & a set of big-tube long-tube headers?