(1) it's swingy. This is either a feature or bug depending on your view point. For me it's a feature. In spite of the swingy nature of exploding dice, it is actually really, really hard to kill a Savage Worlds character. You can put them out of a combat but it's dificult to actually kill them. There are optional rules that can make it easier or harder if you want to utilize them.
It's a feature for me, too, but it definitely means that this otherwise-generic system is only generic for certain styles of play. That's fine for me because I like pulpy action.
(2) High Toughness opponents can be difficult. In some respects this is accurate. There are things you can do to lessen the issue. It can be frustrating for players to swing, hit, and then fail to penetrate the armor/toughness of the bad guy. In my mind it's not different than attritioning meaningless hit points, but I get that it feels different because when hit points are attritioned at least the attacker is doing something.
Yeah, this is an issue that I think they need to address. It does feel like loading your revolver with 5 nerf bullets and one nuclear warhead. Waiting to ace a damage roll isn't fun even if it is tense.
I've seen some people have house rules that every 4 points of toughness over some arbitrary cap (often 11 or 15 toughness) instead results in an additional wound point. It's a decent idea, but I've never tried it.
SWADE is much improved, but this is one area that didn't really change.
(3) Math Bugs - there are some interesting corner case issues with the exploding dice. Notably the d4. It's easier to roll a 5 on a d4 in Savage Worlds than it is on a d6 or any other dice. When the the base difficulty number is a 4, it feels funny. I'll grant that it's a real issue, in that it exists. I don't think it matters because so often you're looking for the raise (+4 over the difficulty number of the roll) to gain an extra effect.
Yeah. The biggest issue is that the math bug is at its worst at kind of a bad breakpoint. The most common dice to roll are d6s and d8s; getting a raise (two successes) requires an 8 or better. Well, it's easier to roll an 8 on a d6 (1/6 * 5/6 = 5/36 = 13.9%) than it is to roll an 8 on a d8 (1/8 = 12.5%). That is an Ace, so it's also true that any raise on a d8 has a 50% chance of being a double raise (three successes) but needing that is often rare. It's a small enough bug that you probably won't notice, but it's still not a feature. You can kinda fix it by simply subtracting 1 from any exploding die... but nobody is gonna do that.
My major complaint is initiative. I hate reshuffling and dealing cards. It's great for Deadlands where the trappings of saloon games are super evocative, but anywhere else they're almost immersion-breaking. The fact that you deal new initiative every turn and have to reshuffle fairly often means it takes a lot of table time just to determine turn order. Having to remember suit order (SHDC) to resolve ties which come up fairly often at a table of 5 (a 40%-50% chance, IIRC) is annoying. And then there's jokers that let players delay and interrupt.
None of this initiative system is "fast & furious" to me. And the fact that there are numerous abilities or environmental effects that trigger on face value or suit means that it's hard to homebrew an alternative. I just don't want a game that cares this much about determining turn order.
My other complaint is mostly about PEG.
They keep releasing fantasy books and I'm really tired of waiting for the Sci-Fi book to be updated. It's basically untouched since the mid
2000s 2010s and is desperately in need of an update. The KS is due any time, but I'm so tired of waiting only to see them release more fantasy crap when I don't think it's a very good fantasy system.
Edit: Typo