Even this local shrines is a bad deal. Other Wards probably won't appreciate us offering this overreach of our authority at all.
How is this an overreach? Tindomiel want permission to add either a dedication or a shrine to their goddess to any waystone they construct. If anything, it's an overreach to
forbid them from doing this.
If Thorek wanted to include a shrine to Thungni on each waystone, would you forbid him?
It's not like we're forcing people to build shrines to Hekarti—the builders just want to include a shrine when they make one. We're not going to march into Kislev and say "we're going to build a bunch of wayshrines and there's nothing you can do about it". They are going to ask us to create one, and a part of that deal would be the inclusion of a Hekarti shrine. And if they don't agree to that, they can't get one—at least, not one built by Tindomiel, at least, and they'd have to wait until we're free to hire someone else to build one. And no, before anyone says anything, that's not extortion. It's negotiation. If we want their mages and priests to build waystones for us, that is the price we want—and currently, nobody else is offering that service. Maybe if one of the Hoeth houses had approached us first and told us what their requirements are for constructing waystones are, we'd have a counter offer, but apparently they are not interested, so their loss I guess.
Now I've mentioned several times that I don't want Elven shrines in human lands because elven gods and human worshippers have a bad history together, but honestly, some of the arguments against Tindomiel are getting ridiculous. If Tindomiel end up upsetting the status quo by building a shrine where it's not wanted, then they are the ones who are going to have to smother that fire. There are twenty other houses on the council, plus the wards, plus the triumvirate. If they antagonise everyone by needlessly forcing their faith down everyone's throats, then they probably don't deserve their position as a major house. Houses have gone extinct before, and their property returned to the crown. If they make an enemy out of everybody, they are going to go down, and we won't do jack to protect them.
And finally, "right of first refusal". How many can they build at once? 5? 10? 100? Sooner or later, they'll run out of resources, or have their priests stretched too thin, and then we have to find another group to build waystones for us. And what price will they charge for the privilege, I wonder?