And then make it blindingly clear to players that the DM is allowed and-or expected to make those restrictions, thus don't assume everything in the books will be open for you to play.
Otherwise, the DM making restrictions comes off as the bad guy, every damn time.
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In game terms, the DM is the external circumstance forcing a limitation.
You cannot have both of these things.
The GM cannot simultaneously be someone with control that,
and also a human merely implementing something they had no control over and thus you can't get mad.
It's either-or. Either you have control, or you don't. If you don't, why is your game so far out of your control that you can't even decide whether something gets included or not? Have you
lost control of your game? And if you
do have control, then why aren't you responsible for taking things away from your players?
You will never get an analogy between something like "we cannot make a game bigger than one megabyte,
so figure out how to make that happen" and "I, the GM, freely elected to remove dungeonrisen from this game". Because the latter is not, in any way, forced.....
except by the GM. So it is perfectly reasonable to say, "Uhh, GM, why did you ban this unobjectionable thing???"
Personal example: 3e didn't have a separate Illusionist class, but I wanted to play a 1e-like Illusionist. I put a lot of thought and effort into how I could use what 3e gave me to build the nearest equivalent, and that's what I played. In replicating a 1e Illusionist the experiment wasn't a smashing success, but as a character she was lovely!
I mean, sounds to me like a lack of imagination on your GM's part. I'm more than willing--
eager!--to put in the time to make something like that work for my players. If I have to draft an entire new class just for their use, I'll bloody well do it. Because nothing--
nothing--is, nor should be, more important than securing the players' sincere, genuine enthusiasm. And, as I know I've said to you specifically before, "genuine enthusiasm" means that it isn't exploitative, nor abusive, nor coercive. "Exploitative" means violating the spirit of the game (be that system, campaign, or table spirit), "abusive" means treating the other players merely as tools to be used, and "coercive" means manipulating others into behavior against their will.
If the thing that would make a player blissed-out happy is drafting a real Illusionist class, then I'm going to bloody well give it my all. Reasonable leeway for tweaking and addressing differences in desired result should be allowed, of course, but as long as I've done my due diligence, going above and beyond "meet you halfway", if that's still not enough, then yes, I'd probably ask that player to leave--because that's
becoming abusive, treating me as their pet designer. Fortunately, I have never once encountered a player like that, and I don't expect to ever do so.