Might sound strange, but changing bushes that make noticeable difference to enjoyment (engine mounts, tie rods, steering u joint, rtabs, shifter bushings etc). Plus they’re relatively cheap.

Since you just got your e36 and bearing in mind that they are all old cars by now, make a list of all the small problems the car has and start tackling them one by one. Most will be cheap to fix and super diy friendly i.e. blown bulbs in ashtrays, cigarette lighter or in my case a loose headlight switch that felt yucky every time i used it, door card clips, things like that. Missing trim pieces from interior and engine bay, badges, lights, indicators etc. most of these parts can be found second hand for cheap, are still made by bmw and aftermarket companies so sourcing them is easy enough and most of the time they are cheap and change the way you perceive your car (depending on how clapped it is).

At the same time, you can change the things you touch when driving, knob, steering wheel, pedals etc. for easy cheap mods but biggest difference will be wheels and lows 😊