Man... I think I'm at the end of my fighting game life. I get so destroyed online it's not even funny. I don't have time to learn sixteen button push/myriad stick motion combos. I don't know if I ever really did have that time? I was always just really good at blocking and countering and that doesn't seem to work in these games anymore.
I really dig the game, and my online has been excellent so far, but it's clear that this genre is passing me by. The rivet counters have taken over and people who play for fun are long gone from fighting games.
Well, I'm in a similar boat. I'm going to quit being competitive shortly- barring any miracle performance at the major I'm going to soon. I don't have the dexterity to keep up. I use a very heavy block and counter style, and it works for me. Maybe I can help you strategically? (Too bad you're XBL). That said, KOF you need a little more active defense- use your CD counter, AB guard cancel rolls, and low B's to counter hops, jabs for jump-ins.
That said, you don't need to do the trials to be effective. I use herp derp combos and can win enough.
If KOF fails, look at less executionally demanding fighters, or maybe try 3d fighters: SC and VF don't require all those button presses usually.
BTW fuzzy guards/option selects aren't really super-needed. They can help, but this isn't SF4, they're not the be all end all of everything. On GGPO I saw fuzzy guard used on me by a grand total of two players, and only a half dozen times in total.
That said, this KOF is much more executionally demanding then 98, though a base of solid fundamentals and pokes can still scrap out wins.