And let's not forget, KOF13 has been hailed by the FGC for being one of those fighting games this generation where it does not stray at all from what made the older games very good and it is not looked at as an "easy" game compared to others out on the market.
Not to disagree with your general point or anything, but there were elements of the KOF community which decried XIII's simplification of 2002's BC system. The fact that the game auto-dashed for you made it far too easy to land these massive combos, taking away from their "wow" factor. I don't agree, personally, but some players do think XIII is a bit too "easy."
Anyway, I think the strengths break down to this:
2002 UM
- bigger roster with more moves
- greater variety in character playstyle (Choi, Chang, Angel and May Lee don't have any equivalents in XIII)
XIII
- graphics
- more balanced (in the console version anyway)
- the system can be used to every character's advantage, without any exclusions (i.e. Chang has no reason to use MAX mode in 2002, but every XIII character can use HD to do big damage.)
- easier learning curve; inputs aren't as strict and Drive Cancels are much easier for beginners to grasp
While both are great games, I'd give the prize to XIII, no question.