Crappy suspension bushes, front wishbone balljoints that give up the ghost at the first opportunity, dire oily shock absorbers and thoroughly crap springs, inadequate specification anti-roll bars, appauling brakes both front and rear (the tiny rear discs and totally hopeless handbrake a standing joke, the fronts barely capable of stopping you at all), not very nice looking Phase 1 half leather seats (how on earth can you use cheap leather on the bum and back and then revolting vinyl sides and back that smells revolting with age), even worse seats in the Momo Phase 2 seats (where you sit ON rather than in the seats, consequently your head hits the roof if you're over 5 feet tall), dire quality carpeting especially in the early phase 1s (carpet material borrowed from the 164), the most appauling timing gear set-up ever created in the known Universe (early phase 1 balance belt slippage and resulting carnage due to inadequate number of teeth, hopeless specification tensioners/idlers made literally of plastic that, hey, tended to break...are you surprised???? Alfa specifying 72,000 mile changes, then 36,000 inspections, then 36,000 changes: result, total confusion), dodgy variators, dodgy quality paint finish with plastic bumpers fading at the first opportunity, hilarious 4 wheel alignment set-up where to get it right you need to adjust the toe in/out bar adjusters at the rear but hardly noone knows about it and consequently 99% of cars are tracked incorrectly. And the usual Italian electrical maladies compounded by Italian artisans and farmers ropped in on an ad hoc basis to construct these cars in the first place.
Apart from that, they're great cars, I really love my Spider. But then virtually everything I've listed above has been uprated, wherever conceivably possible, avoiding at all costs the crap OE bits and bobs.