Don't really have a perfect day or aspirations towards such a thing, indeed don't really even have any contemplations of what such a thing might be.
I also once woke up next to ur mum so there is also the possibility that I will never exceed that.
More seriously. In the realms of things that might happen (send me to go look at a new star/black hole/planet and that will be sweet, but not really an option at this point).
My body mostly still functions just fine and without pain/fatigue so OK with that. No need for a day without pain, mental fog or whatever else as it were.
Don't care about people so wouldn't matter if I met anybody and could see best days being with nobody around, though there are some I might spend it with/would not drag matters down. Sex with strangers is boring as anything so don't care about waking up next to someone attractive or down for anything so for this perfect day that would be a waste of time in it. Likewise I doubt there is anybody out there that I would so massively enjoy the company of/a conversation with that it makes everything else before it seem pointless in comparison -- I have variously met world class artists, athletes, politicians, scientists, engineers and the like before, including in my areas of interest, and occasionally had some fun but nothing more than I have had speaking to a random old person, tradesman or someone down a pub.
I have no objection to good food but it is not something that gets me up in the morning (not that I usually eat until lunch), and not eating for 24-48 hours is something I occasionally do just to amuse myself (24 is nothing, 48 is slightly uncomfortable). I live in my head and don't much care to be out of it, and don't have any vices that drag me down either.
I like solving problems, I like wandering around and seeing new things (be it on foot or skateboard), I like making things, I like fixing things, I like learning things that assist in all the former things. Doing all of those means one probably lacks -- can have fun in the workshop that is not even off house grounds, can also have fun in a cave, exploring a city, exploring a forest, reading a book, at a skate park/spot or climbing a mountain. Likewise "easy" days are boring (if I am ever compelled to go sit on a beach and stay still, it happened once and will never happen again, I will inevitably start contemplating either something I already know, how to build something on the beach or the like, at least until my being a ginger halfbreed kicks in and I burn to a crisp) so would rather be solving a problem, don't have to solve it either. It is not impossible I find something new and very special (so many combinations of things as yet untried, and I occasionally play in things that go there) but that elicits about the same reaction as fixing a random bit of furniture my time spent doing it could have got 15 of those for should I have been working.
Some like free reign to pursue their own projects, however that is 95% of the stuff I do anyway. There are possibly some money no object things to consider but nothing that would set it over the edge really and most things there would take multiple days anyway.
At this point I think I either have no drive to do anything (doubtful but not impossible) or live a charmed existence as it is.
General off topic so song