I don't think forcing the player to make due with what's at hand is a bad design decision. I like the FO3 system of making available good, but in poor condition weapons early in game. If you know that fat man has just a sliver of life left, you are going to either ahve to pony up mad caps t0o fix it, or you are going to ahve to be very careful how you use it. Heavily damaged weapons and low stats tend to mitigate the uberness of these weapons early in game.
It's a bad design decision when I can carry ten different weapons and ten different types of ammo with no obvious penalty (less loot perhaps... but I can still carry enough loot anyway + everything else I may ever need) + it's even worse since at some point I was forced, due to the lack of other ammo, to use a laser pistol with merely a 20% energy weapons skill, which in fact gave me as good a result as my regular 10mm pistol (or whatever I was using) with a small guns skill of about 60%. Therefore I was not really forced to 'make due' but I was rather forced to play a character different from the one I chose, with more or less the same ease & success.
Such design effectively negates any negative consequences from my choices on my characters abilities, making him a jack-of-all-trades-and-master-of-
all by default, which in turn, depends on me to supply artificial limitations to him in order to roleplay, and eventually confuses people into believing that roleplaying is about "eating 3 meals a day", "walking instead of running" and the like.