I can completely relate to you. Initially, I had intended to get Invisalign- mainly for aesthetic reasons. But I found out that I would require conventional ceramic braces after the Invisalign treatment to achieve the best
results. That's when I started to research Linguals more heavily. I had researched it in the past and many people call it "tongue torture" which was why I never considered it but I took the plunge! (again, for aesthetic reasons)
I had my linguals in for about two weeks now. The first 5 days for me was terrible but it progressively gets better. Everyone told me that it would get better in time but I almost didn't believe them... To be honest, the first night, I wanted to rip them out. In hindsight, I have no regrets getting them done. I'm starting to forget that they are even there.
I never had a problem with a lisp but people did notice I wasn't talking like my usual self. I had a terrible lazy tongue. It made me really self-conscious but more recently, I noticed my speech is almost back to normal! I couldn't be happier.
As for the kissing. That shouldn't even be a concern!
My tongue was a bit sore for the first 3-4 days but just remember to drink plenty of liquids. The brackets don't bother me anymore. My tongue has fully adjusted.
It was harder for me to get adjusted to the upper linguals... I thought about lower ceramics but I am glad I didn't go that route. You'll eventually adjust
Hope that helps.