I've had a coin op arachnid dart board since I bought my first pin 16+ years ago. It uses plastic tipped darts, and for the past several years I haven't had it right next to any backglasses, so I've never seen any breakage. I like having it. It mixes things up a bit, and some guests are more into darts than pinball. I'd recommend it.
The footprint is also way smaller than a pinball machine so if you can find a space that a pin won't fit but a dartboard will, that would be ideal.