Last year I put about 200 km on my E30 after I got it on the road in September.
I drove carefully with-in walking distance of home - you know - just in case.
Last Sunday I put 190 km on it, 80% or so highway, and after a few miles I was driving the heck out of it. I liked it and so did the car. It revs better, it shifts better and it's just... it's ... well... it's a car now, not a museum piece.
It's soooo much better now. In a week I've not quite doubled last year's mileage.
So, my sage and profound advice is to stop working on / fussing over your car and fretting over that odd little hitch in the idle or the spot of oil near the franastat grapple grommet: it's spring! Just go drive it!
(With thanks to The Twin for giving me a reason to take'er beyond walking distance.)