Heh. The player also wanted a steam-powered Harley Davidson.I certainly applied rule-zero there! Nothing wrong with that idea, by the way - but not in this campaign. For one thing, there are no serviceable roads, and they live in a swamp, so the vehicle would be abandoned/written off in session 1...
The player in question is very enthusiastic about her character concept, and I'm happy to bend the rules of the setting (bend, not break; no Harley) to accommodate the players' ideas. In the past, I'd have said "no". Now I'd rather say "yes" than "no". As DMs, it's great if we have enthusiastic players (I am lucky to have four very enthusiastic regular players), so I certainly want to work with them when I can.
I don't think Gnomish tech will cause any problems (my conclusions on this are set out above). The tech does exist in my world, just not in the area they'll be playing in - so there's ample justification.
I'm currently in the process of setting up a new 5e game, and I (perhaps) made the mistake of saying that players could pick any official races and classes. One player has gone for a gnome, and now I've got to get my head around all this clockwork nonsense works.
The main issue I have is that clockwork is a massively advanced technology for my world. It's not like magic, where some character can just do it while other can't: if Gnomes can make it, I don't see any reason why everyone else can't reverse engineer it and then churn out clockwork devices. Then you have a world full of vastly advanced tech. Presumably that isn't the intent (or effect) of this in most 5e games. So how are we actually meant to get this to make sense in our campaign worlds?
I would like the player to be able to play the character of their choice if at all possible - so has anyone else managed to make any of this make sense without huge elephant-in-room contradictions?