I think one reason Roy does
I think one reason Roy does not just make TTW into his personal vision, Yossarian, is because he is part of a team, and all the members have their own vision of the game. You can make Nevada Skies however you want, because you are the sole owner of the mod, and are thus beholden to none. It would be a rude for Roy to try to force everyone else on the TTW team to submit to his vision of the mod. They are all woking on this project together, and need to make something they can all enjoy.
As for your comment about game developers not giving options, I rather disagree. Most games have a difficulty slider, and many have other player-selectable features. For example, New Vegas has difficulty adjustment, Hardcore mode, and Wild Wasteland, allowing each and every player to chose their personal preference of how silly, how hard, and how realistic they want their game experience to be. A very hard, hardcore, No-WW run is very different from a normal difficulty, non-hardcore, WW run, for example. Or from a hard, hardcore, WW run, etc.
Certainly, there is no obligation for any developer to provide optional features, but in most role-playing games, such features allow the game to appeal to a wider audience and are beneficial to the community.
A short list of TTW optional features which I think the community has GREATLY benefited from having: Startup Menu, Bobble Heads Changes, and Reputations. If any of these files were dropped, the TTW player base would inevitably shrink due to disagreement with whatever choice the team made.