i have added an anti-blue gelatine-filter(81a?) inside the film chamber. its enough space. slide films are blue. maybe not never ones(older ektachromes).
i had never problems with over or underexposure. i would only use it again with colornegative. new fuji natura 1600 is sensational. together with the camera of the same name(24/1.4 superbe lens-250 usd). you will be quicker and better than any other digital photographer...there are some sites around with images. only available in japan or asia.
I think the camera given its size and age is a pretty good deal, i aggree with the points u make but this was pretty much ground breaking at the time and be fair how many slr's of that age are still plodding on, the xa is out pricing most aged slr's on ebay now, my canon if sold wouldnt recover the cost of the flash gun in the kit. Best to take it for what it is, a well rounded 30 yr old camera which in honesty offers standards that many modern packages still struggle to better,