I think as part of your challenge, you need to establish a clearer "goal".
For example, (my personal opinion is that) Kirian's "educational set" would be a disaster to teach new players with. So the education part only would be good for players with a few games under their belt.
Whenever I teach someone the game, I actually find the best way is to play with:
Copper
Silver
Gold
Estate
Duchy
Province (only 2 of each per player playing)
Smithy
Woodcutter
Steward
Laboratory
Anything more than that is generally confusing. We'll play a quick intro game, then I'll start adding in more kindgom cards 2 (or so) at a time. First two are usually Witch/Miltia, then Remodel/Village, etc. Once they get the hang of the first set of 4 cards, it's a lot easier to baby-step them into new types of cards (attacks, filter, "remodels", action chains, etc).
I find that teaching too many different aspects of the game at the start is just overwhelming, especially for non "gamers".
I've even managed to teach my 4 year old son how to play dominion. We started with just money (not even point cards). Over a handful of games, he's actually able now to evaluate 10-card kingdoms and play a full game. He actually wins surprisingly often! (he loves himself a montebank/witch!)
I think you started on the right path with defining your goals, but you should elaborate more on what the purpose of the set is... possibly giving consideration to giving out a "rating scheme", such as:
/2 + Multiple Strategic Routes to Victory
/2 + Killer Combos
/2 + Underused / rarely purchased cards more useful
/2 + Overused / frequently purchased cards balanced by other options on the board
/2 + Educational (Playing the set will allow players to better get a grasp of card nuances)
Total /10
The reason I say this is that the above scoring scheme will create kingdoms that are good at lots of stuff, but not extremely good at one.
A better challenge would be to just include one (or maybe two) categories. For example,
/5 Educational
/5 Multiple Strategic routes to victory
/10
I think that "goal" inspires "better" kingdoms for the specific criteria.