Personally I would say go back to M0 or M2, or even normal raids. 480 iLVL in an M5 this season is equivalent to 440 iLVL in an M15 last season, in other words, a fresh level 70 who has done minimal overworld content, some of last seasons low low keys, and some normal raiding trying to do an M15.
Equivalent exchange would be doing an M5 at 500-510 iLVL before pugs will accept you and the only reason you even got a group was because you started your own.
It’s the same problems making a key and joining a key, at your iLVL doing what DPS you can do, some people are going to take note and leave because it’s just not enough to push keys. And some people will check your iLVL before the key starts and leave to not waste time.
People do this all the time joining keys, the only difference here is that you started it, you can invite people to your key, you have a higher chance of the key starting and finishing, but whether it will go well, maybe not unless you bring in some 510+ iLVL players.