My 95 rs is at 147xxx right now and the past couple owners apparently were complete dumbasses with the maintenance (or lack thereof in cases) on the car. As Ive had the car for almost a year as a project, when I roll it out this summer I intend to have it running optimally. I have every intention of getting a new intake (I hate goin stock) already got 10mm spark wires, debating what plugs to get. Already have catback and ordering new cat, upgraded to rear disc brakes. Other mods too cant think of them.. But Im debating on my tuneup options..

~Motor oil: I know royal purple is the highest recommended, but in an rs, is it worth it? Will I get a noticible benefit from going synthetic? And what weight would be optimal?
~Trans fluid: Should I do a tranny flush? And if so, again, would synthetic be a good choice trans fluid? Im running an auto trans.
~What spark plugs would be best? I dont wanna go the extra mile with 10mm wires just for economy plugs.
~Any other tips for having her run as best she can?

I know I can go to advance or autozone and ask people there, but they also told me my car isnt obdII. Id rather get the general concensus of those who know what theyre talking about.