I wouldn't suggest slitting them open, or using loose snus. That would endanger your atomizer. A mini pouch of snus fits well in a penstyle cart. I haven't tried one in my other e-cig carts, simply because I ran out of snus and am ordering more!
Alcohol will just not make good vapor. No doubt a reason PG was chosen (in addition to cheap cost) is its ability to vaporize well and act as a carrier for nicotine. VG does the same, but is sweeter and actually makes even more vapor. It's also more expensive.
If you have a problem with both PG and VG, I'd say this is not for you. I'm not aware of any other safe vapor carrier.
When I went to put the soaked snus into the cart, it seemed too big. So I pinched down one end and stuck that in the cart, then "screwed" the thing into place. I poked it into final position with a pair of tweezers (but be careful not to tear that little bag).
The original VG lasted about 8 hours of regular use. I put some more VG into the cart, but the flavor wasn't the same, so I'm moving that Kissbox back to regular carts I have on hand. This might be an "emergency" way to get vapor -- and I get the bulk of my daily nicotine from snus, dissolvables and puffing a pipe. I don't view this as my everyday way to vape.
Now if some company put out little dry, cylindrical bags of pure snus tobacco .. ones that fit exactly into carts .. and we could add VG at our end ... well, we'd have a tobacco-based e-cig for sure.
I bet the anti's would freak out more over that than they did over our liquid with nicotine in it!