Been there done that! In fact I posted about the same issue a couple of seasons back. I know exactly what you're dealing with. I love to throw gurglers and all maner of surface nasties that are all aerodynamically abyssmal. They just wouldn't work the same if they were
And its true that heavier tippets are less affected.
Last season I was describing this same problem to a conventional fisherman and mentioned how it screws your cast up like using a spinning bait without a swivel. So, he digs in his tackle bag and pulls out the tiniest swivel I ever saw. I swear it would struggle to sink a size 28 olive emerger and was rated 30lb
I picked up a few at a local store and will be trying them out this season. Even with the smallest warmwater popper I have no concerns over the weight of the swivel compromising the action of the popper and if my early-life spinning experiences are anything to go by, the problem is fixed. Watch this space for results