The problem inherent in your request is that how many WHMs are exping at a certain level fluctuates on every server over time. Right now on Lakshmi it's like pulling teeth to find a WHM at most levels, but a month from now there could be a ton. I see it happen constantly.
I suggest you stick it out on your server, unless there are other reasons for you wanting to leave (like problems with other players or whatnot). The best thing to do is put details in your search comment - like when you ding 40, let people know you have Haste (some people don't know what level it is, it'll make you a more appealing choice, and if you advertise you have it maybe you'll be more likely to use it). Let people know you have Erase (though it's not expensive anymore so people should expect that all WHMs have it). List what levels, if any, you're willing to sync to. List what areas you have access to (if all areas, say all areas).
As a party leader, I tend to go for people with search comments before I go for someone randomly seeking with no details because its more work for me to have to ask them everything and it's annoying to get my invite turned down because I'm asking them for a level or zone they can't do.
____________________________Morwyne ~ Lakshmi
PLD WHM BLM BRD RDM DRG SMN RNG NIN BLU SCH COR WAR THF ~ Retired