I play DCSS in tiles mode and DF in ASCII mode. It's not that I think graphics are a bad usability feature, I just think they're over-emphasized because they're the first thing people see.
Adding graphics to DF means more new players give it a try, but most of them are going to bounce off of the wildly inconsistent menus. It's an acquisition funnel thing; the total players will be incoming players times the percent that are okay with the graphics times the percent that are okay with the menus. My assertion is just that in DF's case the menus have room for a bigger lift, because they're really that bad.
Adding graphics to DF means more new players give it a try, but most of them are going to bounce off of the wildly inconsistent menus. It's an acquisition funnel thing; the total players will be incoming players times the percent that are okay with the graphics times the percent that are okay with the menus. My assertion is just that in DF's case the menus have room for a bigger lift, because they're really that bad.