I have a single coil in my 50's Maton Lap Steel and that thing honks, its an old Fender style single.
Is it the dog ear or the stock P90? probably could flick the magnets and smooth it out a little with some A5, remembering there are good ceramic pickups just as their are bad Alnico ones.
I know some of the SX pickups are pretty lifeless, but the cost of these guitars and lap steels, they arnt expensive, so i dont see the point of putting $100 pickup in a $100 guitar. Having said that i took the bridge P90, (very bright and bighty) out of my Agile 2200 JR and put a Rory Gallagher made by Kent Armstrong in the bridge and it transformed it, but they cost alot.