WarpMyMind

If we use the alternative name "monoideaism" for hypnosis

Then I would suggest that you trigger or anchor the response you want to each of those individually.
I would go for a powerful response to one of them

Then add the responses for the other two.
That is to say a file for "cocks", used for a month or so until the response is powerful
Then add the others riding and revivifying the strength of feelings for cock

I'm sure you can load a dozen different things into a file or session and while on the surface I might do that
In practice I tend to have one goal for a specific session and everything works toward that

Think of it like this. How easy is it to learn Motorcycle Repair, Calculus, and Judo all that the same time. Somewhere something is going to get lost and you're going to end up trying to install a head gasket on your Judo instructor. If you overload yourself with too many suggestions at once, especially different ones your mind isn't going to be able to focus on them all and something will be lost.

Okay lets say you focused on one fetish until it becomes deeply rooted in, but without exclusive language to that fetish.

So instead of "You only find cocks extremely sexy...", it's in non exclusive language such as "cocks are extremely sexy...".

So after that cock fetish becomes deeply rooted in, and you now move onto a new fetish, this time lets say a booty fetish, also in a non exclusive language "bums are extremely sexy...". and you deeply root in that fetish too.

The question is, will the second fetish for bums diminish the power of sexiness of the first fetish for cocks. Or will they be as equally as powerful as each other without diminishing the power of sexiness. So cocks and bums are 100% sexy each just like when you first developed that fetish, vs now being 50% sexy each.

I would say, with at least my own experience even before hypnosis. It might not be able to make things as powerfully sexy compared to if you just focused on one. Even before hypnosis, I went from fetish to fetish usually, and once a new fetish developed, the old fetish faded away naturally. It didn't matter whether it was heterosexual fetishes for anal, fisting, bbws, big clits, wives, milfs, to eventually a trans fetish for shemales, and then sissies (all before erotic hypnosis). Once I got into shemale porn, getting turned on by any straight porn had long gone.

Anyway I'm just theorising here, I have no idea what's true or not. But I feel at least in my case, it's hard to strongly sexually enjoy multiple fetishes at once (even when developed separately over time), as I can when it's just one.