I wouldn’t make too much of Wham’s ease of use. 90% of the cast in this game has insanely low execution requirements.
Turtling is still the nature of many matchups in this game, even post-1.03. So much stuff is negative on block and avenues for mixup are so limited that a lot of times your only choice is to poke sparingly and either take a step or two back or vertical jump to attempt a counter-poke. This is true of many characters, but it’s especially pronounced for the shittier ones like Kars.
Kars is really kinda screwed in that regard pre-Ultimate Being because his normals are so-so, and they’re almost literally all he has. His 5M has too much of his hitbox in it to clip limbs with, same deal with his 3H for anti-air. His jab doesn’t reach very high and his 2L has mediocre range. Same deal with his jump-ins – decent depth, shitty reach. All of this would be cute if he had ANYTHING else he could do at different ranges. His specials are not great mid-range whiff punishes. He has no fireball and shit for long-range whiff for meter build. His rapid slashes grant shitty advantage on hit (maybe negative on hit? I’ve never checked) and are almost never worth the meter to make unblockable in Light Mode. And of course his teleports are suicidal against anybody but your 8-year-old nephew.
So your options as pre-Ultimate Kars are pretty pathetic – inch close to your opponent’s max poke range and pray they’re impulsive enough to whiff something you can tag with 2LMH or 5LMH into crossover slash. If you have a decent life lead, you can stay in to fish for more meter, or you can cut your losses and fall back to block and preserve your life lead. Those are really your only options against somebody who actually knows how to play the game.
Wham is not super, SUPER-well-equipped in these department, either, he just SEEMS a lot better because Kars is so incredibly shitty and deprived before he gets his wings. Wham has a much better focus (be okay until your bar lights up, then be good) than Kars (be shitty until your bar lights ALL the way up, then be godlike if you’re lucky), and it shows. From damn near the bottom like pre-Ultimate Kars is, EVERYBODY looks scrubby and godlike.
If you want productive advice vs. Wham, I would say try to space him out and get him to whiff jump-ins, I guess. Wham’s jump-ins have big range (particularly jH), but they take a while to go active, and with good spacing you might be able to tag their landing recovery with an LMH whiff punish. Safe jumps after crossover slash might also be helpful if Wham really likes to wake up with something. Don’t jump at him when he’s standing up, try to get to a range where he’ll either be tempted to jump at you or come in for a jab, and experiment with whiffing inconsequential things like 5L / 2L to invite him to attack you on cue. Footsies are everything because they’re all you have. And if you still hate Wham, look at it this way – you could be fighting Caesar instead. (why, why, WHY do lenses have a hitbox that KNOCKS DOWN before they fire?)