Fudge.

So, for the longest time, I only played T&T using solos, because I didn't have a regular gamer crowd. Also, for a long time, I wasn't anywhere near a game store that carried T&T and I didn't have much in the way of disposable cash anyhow, so I actually only had two solos: Buffalo Castle and Sorcerer Solitaire.

I treated both those solos as "testing grounds" for new characters, and then ran them through randomly-generated solos of my own device, or based on the random dungeon in That Other Game's GM guide... but this led me to try to open things up a bit by, well, I guess, cheating.

Things I've done:
I've run rogues through Buffalo Castle (forbidding them their magic.) Likewise, wizards whose fighting chops seemed sufficient.

I've had my own wizards sell spells to rogues. Extortionately, but they've done it.

Oh and! I tend to allow myself one re-roll per game.

Things I need to try:
Thinking in terms of solos, like Sword for Hire, where the delver gets a companion  for the journey, I'm thinking it's not to big a bend of the rules for most solos to bring in a hireling or two, derived as per the book.Such an arrangement would only work for hiring bring-along muscle for fighting: the player would still have to take point (any hireling taking point would certainly run more risk, and rate better pay, and would in any case benefit from most of the magical gimmies.)

There's a nifty card game called Space Pirate Amazon Ninja Catgirls which breaks the game up into "capers," each caper has a loot reward for success,  and is broken up into four "challenges." It seems that a sort of abstract solo could be handled the same way:

Each "adventure" has 1-6 challenges.
A challenge can be 1-3 a monster encounter, 4-5 a "trap", or 6 both.
Each challenge may (1-3) have treasure

Upon defeating all the challenges, the delver(s) receive a further treasure.

Higher levels bring tougher monsters and higher level saves for the "traps"; also, more treasures.

Traps represent puzzles, traps, or other obstacles: roll 1D to determine which Stat it should be based on. The player chooses the adventurer to attempt the task: failure should result in taking hits, at the very least.

More as I think on it...