I want you to open a Gate to Valinor. - I'd really like four, but that's more than we agreed on. I want to send orcs there. It will advance my interests in three ways; first, it will force the Valar to either declare outright that they will kill innocent people in their paradise for being ugly, or to forcibly round them up and ship them out, or to set a path by which people they consider imperfect can exist in paradise. I think they're reasonably likely to do one of the first two but I'm not confident, and I've been surprised a few times by how far they'll go for peace and quiet in their paradise, and so it might be the third, which would be - a significant step towards some sort of negotiated peace. The orcs are volunteers, and aware the Elf-gods will plausibly just kill them.
Secondly, this will distract them for some time no matter what they choose, and buy us more time before they invade Beleriand again. This is a critical priority; the last war sunk a continent and this continent has a lot of people on it right now.
Thirdly, it will delay your friends in preparing their offensive against us. I do not see any plausible mechanism by which it could endanger them. But they have declared their intent to sell the libraries of Valinor to the Dwarves for weaponry and they will be delayed if the Valar close free Gating in and out of Valinor, which I expect they will in response.
The reason I'd like four instead of one is because if the orcs are scattered across the continent it will take the Valar much, much longer to respond.