Hi, Ukejenny!
I am in the same boat as you! My story is that I just bought a Martin T1K and it came with the Martin M620's for the tenor; I like the strings, but I, too, was wondering if there might be something out there that was a little more "buttery," to use your word.
I also just had the action adjusted on my new Martin, so that is good, too, but I still feel like I wonder if there's something "lighter" for strings. I learned that to have this (lighter strings), it means sacrificing tone, as my good friend, Stan mentions (and told me, too, when I asked for his advice).
The uke that I recently just sold had the Worth CMs; I really liked them, too. I think, for me, the Martins feel a little lighter than the Worths...but, I am just a noob who doesn't really know much about what to look for or expect. I only know that with my fretting hand/wrist issues of pain, etc., I need something that requires very little effort with respect to fretting.
I just ordered a set of PhDs from UU a few days ago; I will also be ordering the strings Stan mentions, Oasis and Salverez. I also ordered another set of Martin M620s, too.
Let me know what you think when you try out your strings and we can compare notes! I would really love that!
Happy strummings!
~ Chelle