First thing first, welcome to the forum.
Here are some of my tip for ya.
- Drive - Drive this car. Without driving, you don't know what upgrade you need.
- Purpose of This Car - What are you trying to accomplish from this car. Show car? Weekend warrior? Track monster? Autox Master? Drift King? There's millions of option here. You decide what you want to make this car. "Functional" have very vague word. What kind of "functional"? Cuz drag "functional" & drift "functional" is totally different thing.
- Grain of Salt - Listen/Read all the member recommend as a grain of salt. One mod might be awesome for one member doesn't mean it is for you either. This is YOUR car, not other member's car.
- Search - There's A TON of. Great information in this forum that member & vendors posts. Search & ye shall receive.
- Local Meet - Meet & greet w local members. There are usual monthly or quarterly meet around you (hopefully), so check regional section. Meet w your local member & see/hear/feel what kind of mods they have done.
- Try New Things - you wrote this is your first RWD, then try new things. If you never been to autox, try em out! Don't need slick tires, BBK w coilovers. Just try out stock & see if something you wanna do THEN upgrades. Never done drag race? Go to local track & drag race. Hell, you won't win much, but you know your car need more & know that it needs power. Do canyon cruise! Take an awesome pic at top of the canyon! Do new & fun things (that's legal).
These are my tip & I'll leave you w Tada-san's tip (Toyota Chief Engineer of FT86 Concept)
"Design/create your 86. May be just a small sticker on the window or full engine swap. 86 that show who you are and proud of."