Alrighty, this is my first post on rcuniverse, hello all

So here's my situation. I have an old Futaba FP-T4NBF radio and receiver with a couple servos that came out of a plane me and my dad had built about 14 years ago.
I wanted to slowly get into flying without breaking the bank....I'm thinking about getting a GWS SlowStick or maybe something else someone can recommend.
I want to use the old Futaba FP-T4NBF for this setup and I'm assuming that the servos and receiver I have are too big and heavy for the SlowStick...is that possible or is the radio just too old to be compatible with newer and smaller receivers? I've done a little research and it looks like its possible to use the Futaba, just want to confirm. Also, is it worth buying a flight pack that includes the ESC, receiver, and servos or should I piece the flight pack together myself? Reason I ask is that I want to make sure I buy quality components, and I had also read that some of the parts that come with these flight packs arent all that great, such as the battery back weighing too much and the ESC being too low amperage. I hear that you can use a few different size servos with the SlowStick, I want to make sure I get servos that are compatible with other planes as well. Are these tiny receivers and servos only good for using in small airplanes or can I eventually swap them into something a little bigger than the SlowStick? Thanks for any light you guys can shed on this