I have never found French lace to be suitable for an exposed hairline. You need Swiss, so you are going in the right direction. With the French, if you cut the excess lace off, you can get a passable look which you can partially expose.

I agree a photo would help us diagnose the problem (blank your face out if you prefer).

One thing which may help is to use more layers of glue. Lace (of any type) disappears by sinking into the glue. French lace is coarser, so it needs more glue to sink into.