I'd love endless mode too, or even just Long Game modes, the same as random mode (both normal and hard) but with maybe 50 levels instead of 25. I get that there might be limitations that make that impossible though.

I had this same thought, but my ideas for such a mode are a bit more elaborate so I'll offer them. | The mode should start out childishly easy and ramp up to greater than hard mode difficulty by level 100+. | Levels can eventually be much larger than the largest the game currently presents -- to the point of almost being legitimate adventures in their own right. | Rare or zero access to "win button" presents like Reveal Map, Icarus Wings, Duplicate Present, Instant Promotion, etc. | Amped presents and the Amp Present present aren't even seen until later in the game, and are prized possessions because of their scarcity. | No metered cap on leveling, so things like inventory space and health bar can continue to duke it out with the increasing challenge. Other things like speed should of course maintain a cap. It shouldn't be permanently possible to outrun everything without using presents. | Enemy types later in the game perhaps enhanced with further palette swaps to indicate the increased threat. | Reduced and/or gradually reducing access to "instantly lose aggro" good earthlings, and a tighter control over what the menus do to earthlings who have already spotted the player (no more abusing menus to make them forget). | Wiseman steadily increases his price for identifying presents, and again, little or zero access to the Identify present. | Later levels very definitely stop having a guaranteed walkable path to the elevator. (Though it should still be accessible with Hitops or Spring Shoes.) | Perhaps a Sword Art Online-style system of respite levels (every 50, 100, whatever) that mirror the characters and features seen in level 0. | IMPORTANT: Have both fixed (official) and random iterations of this; some people, myself included, prefer the sense that they're challenging something on an even playing field, rather than something arbitrarily arranged and thus theoretically harder or easier than what others are playing. | Again, these are just ideas, but the game already has so much potential here that I felt it'd be a waste not to voice them.

25 is good for me. each level is already pretty randomized

I agree with this, would be better than just a 25 level game each time