Because we can't please everyone, lets please no one.
Well, relay browser changes have gone the route of "let's make everything a preference".
Why is this? Not only are relay browser changes considered "invasive", people are used to the idea of using Greasemonkey in conjunction with KoLmafia (so Greasemonkey does cool things with some pages, KoLmafia does stuff everywhere else) and so will disable every cool customization we put in the charpane if it breaks one of their Greasemonkey scripts. No way to turn it off? There will be a feature request to ask us to let them turn it off pretty quickly, so think ahead.
With that being said, I don't like adding a feature for the sake of having more features; I'd like to know why it is that we put that feature in there in the first place. Sure, the native UI has it because someone took the time to leverage that screen real estate (which was really just empty space due to the size of the panels to the right of it) to make maximizer more intuitive to use. But, is it necessary in the relay browser which doesn't naturally integrate with maximizer, and if so, why? What about it is useful?
By opening up that discussion, it also opens up the discussion for an alternative way to implement it (like ChIT, for example), and maybe it'll make a lot of things easier down the line if we refactor first in preparation for several changes instead of implement each change, one-by-one, head on.
I want to try to move to using a webUI instead of the standard GUI it would allow mafia to be run on more devices and thus help more people.
I like the idea of this, but it doesn't mean we'll accept every single change you want to implement as-is to make it possible. There will be some code massaging, there will be some discussion. Does it slow things down a lot? Of course, but as noted before, a few changes here or there aren't going to cut it. If we can do some refactoring instead of new feature implementation to achieve it, it would not only ease
your attempt, but it might make things more interesting for everyone else as code simplification means that more people can get involved.
If "half-tempted" is serious, as opposed to rhetorical, then I would find that very interesting. Though I think it should not be enabled by default. Perhaps a preference called "use WebUI" and such relay optimizations as ChIT would be a good beginning for the totality of what the setting would enable.
Depending on how cool ChIT actually is, I would make it the default and make people opt out of it, because I like making people blink twice and go, "Holy crap, who in the world comes up with these cool things that the KoLmafia team keeps adding?" I'll have to play around with it and look through what it does before making that decision, though.