The full details are TMI for the profile, but you could definitely call yourself a widower. It's subtle, but people seem to view them differently than the divorced or forever single and you might as well take advantage of that.
I really like your performing photo, so it's unfortunate that it's older than the others. Keep it anyway though, because it's good. I'd eliminate the photo of you in ill fitting jeans, because those pants and the busy background do you no favors. Also not doing you any favors is the one with the Guinness glass, which seems to focus on the shelves rather than you. Do take some new, flattering full length photos though, because they'll help. Watch your expression and your background, please.
Except for some tweaks, I quite like your profile. You seem likable and solid and that will be helpful over the long run, as you build at least a small circle of friends.
Many of the tweaks are punctuation related. I'm trying not to sound harsh, so let me just fix the first section instead of telling you what's wrong:
"I'm looking for fun, smart, sexy, 50+ single women and couples for some lifestyle adventures. Whether you're newbies, experienced, or something in between, everyone's welcome (I have an equal opportunity libido)! It might be a one time thing or could become an on-going FWB situation and I'm open to either."
And I could be convinced that a period would be an improvement over the exclamation mark.
No, actually, I'm going to have to say something else about your punctuation. That's not how ellipses are used. Find some other way to connect your phrases, please.
In Description, after you've ditched the ellipsis, if you eliminate "Physically" and "Personality," along with that throwaway line about pain and pee (how many people have asked you to pee on them over the last however many years you were in the lifestyle?), you're good. It works and you sound like a fun guy with personality.
In Fantasies, because it's awkwardly phrased and doesn't really add anything, you can lose the phrase about the pub conversations. This is also possibly the most graceful place to note - where you talk about experience as part of a couple - that you're a widower. Otherwise you're good.
Additional comments is full of personality and a solid way to end. Just take the capital L out of Lifestyle and you're good.
Honestly, you're over 60 and the opportunities for a guy your age are somewhat limited on line. I think you'll do better once parties and clubs start up again, because personality and experience trump age in person in a way they don't really have a good chance to do on lifestyle sites.
Good luck.