Actually I was in the same stuation with you but ı decided to change my setup to s95 for a better alternatives for wideangle.
But I made a research about big eye lens (and smilar lenses) before ı decide. So everbody says that you can only get 80 degree field of view with this lens. And you can have a glare problem when you try to take photo against the sun or light source.
Becasue there is no glare coating at this lenses.
G11 is much better for macro purposes. You can buy a mount for wpdc34 housing for macro lenses but wide angles. When you try to add regular wideangle lenses(like inon etc) to wpdc34 housing with a mounth you will probably have vignetting problem.
Thats why I sold my g11 and buy s95 ıt was a hard decision but now I have better wideangle options.
On the other hand you will pay about 257 usd for these kind of big eye lenses but ıf you can change your setup to wpdc38 and s95 you can buy Inon lens around 400 usd with the capabilitry of over 100 degree view of field and dome port II option (which will give you around 130-140 degree FOV)
Im not an expert but I made some researchs...
I hope it will helps.