2_8B+K should step all verticals at neutral & roulette, from instant input to end of transition.
SC4's 2_8B+K can be hit by almost all verticals regardless of timing & is because timing is the problem. Most Sig's into-stance moves on Guard leaves him at specific frames for some 2_8B+K dodges to work, but all characters have at least 2-5 verticals that hits Sig during (early or late) 2_8B+K, leaving him back turned most of the time at disadvantage, only rely & prey that your opponent's next move to be a horizontal & not a vertical or a throw.
2_8B+K should have instant, reliable dodge regardless of frames & range, its supposed to be an option against opponent's momentum, not a move with lots of mistaken programmed advantage for your opponent.
2_8B+K (and all dodge or tech step related move should in all characters) should dodge just like Yun's B+K'n (without the idle-auto part) or like Kilik's 1B or Ivy 214B or Mitsu's 4B+K'B. 2_8B+K should make Sig invincible against verticals from the moment the input is pressed to the end of transition. Sig could also have 2_8[B+K] hold option where he could double side spin to dodge multiple quick verticals like BBs (where in the case of "2_8B+K vs BBs" the 2nd B would hit Sig most of the time).
B+K's GI should impact instantly after inputting B+K & should impact full-time.
SC4's B+K doesn't impact instantly & the GI effect goes OFF when Sig is sitting down for few -enough frames to get hit by horizontals- then the GI effect turns ON again for the Reborn Basher auto counter. This is ridiculous, Sig has an all horizontal GI move that doesn't GI horizontals at a specific in-between time, while the visual effect stays ON, the effect does NOT. I've gotten hit many times by horizontals while trying just plain B+K (not pressing anything afterward). I'd research on Training mode & found out of its OFF-frames. This is stupid from NAMCO's programmers, why does this happens? Why add a GI move that fails to GI at a certain time? Why add a GI move with demotivating effects? Is it for use or not to be use? Since I can get hit on counter by verticals already, why make it like this? Is just plain stupid.
B+K should impact instantly at neutral & roulette situations. Sig should have the OPTION to GI horizontals at all times during roulette instantly upon opted input. 3B,B+K, 22_88B,B+K, 11_77B,B+K etc.. should all be legit 100% reliable OPTIONS.
Fixing those will improve Sig's game without making him overpowered or win friendly. This will just make his Horizontal Impact/Dodging game actually legit & practical while still been an optional mixup factor. Back in SC2 NM (Sig) had the "G2 glitch" to guard instantly after doing 3B or other into-stance moves, it was a broken factor because it covered both horzontals & vertical in one input, G2.
But by FIXING the attributes or/& properties of both 2_8B+K & B+K, Sig can have a two-way gamble mixup & not being as "broken" as SC2's G2.
Sig vs Xianghua example:
Sig does 3B, X guards, Sig does B+K, X does AA, Sig Impacts X's AA.
Sig does 3B, X guards, Sig does 2_8[B+K], X does BB, Sig dodges X's BB.
Sig does 3B, X guards, Sig does B+K, X does 2A_B+G, Sig gets grabbed by X's 2A_B+G.
Sig does 3B, X guards, Sig does 2_8B+K, X does AA, Sig get hit by X's AA.
IMO, to have ^^those^^ even-possibilities ^^from above^^ is better than:
Sig does 3B, X guards, Sig does nothing, X does AA, Sig gets hit by X's AA.
Sig does 3B, X guards, Sig does B+K, X does AA, Sig gets hit by X's AA.
Sig does 3B, X guards, Sig does 2_8B+K, X does AA or BB, Sig gets hit by X's AA or BB.
Sig does 3B, X guards, Sig does SCH'K, X does AA, Sig gets hit by X's AA.
Sig goes to Namco's office & ask: hey wtf?, X comes out of the office & AAs, Sig get hit by X's AA.
This idea is not just for 3B (as for I don't use it anyway), this idea applies to all Sig roulette, I'm just using 3B for plain example of how bad programmed Sig's 2_8B+K & B+K are, & how it would improve the balance mixup for Sig in those situations where there's no mixup, just plain punishment which leads to some move to go unused for the sake of winning. Winning, but with no fun. Tourney matches goes like AA, BB, AA, BB..., hey! what a fun game! :/
4B+K'A+B or SSH'A+B should have less recovery frames to make it safe or to give advantage on Guard, it is after all a retreating slow low with no forward range that leaves no combo & no RO possibilities, why does it have to be unsafe (-20 on grd) specially on whiffs? IMO, it has too much recovery frames after hit frame.
Mitsu has his 4B (-14 plus cancel into MST option), X has her 44B (-19 plus H/M IMP option), Kilik has his 4B+K (-12), all of them auto-steps/jumps back & forward from easy fast input while Sig's just moves backwards from entering into stance first. I mean, what? lol.
Sig could have stance options during or after SSH'A+B:
How about SSH'A+BG to cancel into Back-turned SSH, it could work nice even for dancing loops (SSH'A+BG, BT-SSH'A+BG, SSH'A+BG...). Perhaps a late Just Input with G to cancel just after the low back hit comes out canceling the front hit only, it could be for a back-turned combo like BT-SSH'A+B:G (hits), SSH'B or A+B.
How about SSH'[A+B] to go into RSH. If SC3's RSH'A comes back this idea would be great for range set up after hitting with SSH'A+B.
BT-SSH'6B+K back-turned forward jumps should be available for normal SSH' to back jump like SSH'4B+K, 4B+K, 4B+K.. until opponent catches me, HA!
SSH'B's GI should Impact High horizontals the entire time his sword is in front of him instead of just during short brief frames at start up.
2A+G Flap Jack, after flipping & knocking down opponent, it should leave Sig at +22 & far enough to give Sig time & distance to mix with 6B & 2A+B. I used to do it in SC3, Flap Jacked opponents couldn't roll away from 2A+B, it forced them to get up crouch guard, it was sweet :)
236B should have cancel options into stance, for example: 236B to cancel into SCH. Or 236b:4B+K to cancel into SSH.
SBH'[K] should have follow up inputs 2 or 8 to steer Sig's run to the background or foreground, similar to Cerv's 124'2_8B or/& Asta's 33_99[K]. This could allow YOU to manually chase your opponent, which would be fun, & possibly to purposely whiff the last hit to back-turn Sig for more (or/& actual) back turn set ups.
22_88A's input should go back to 77A along with 3A as 33A, both should be i25 with instant TC & -9 on Grd.
I got more ideas, but these are my main concerns, because I know that if at least Sig's B+K & 2_8B+K were working properly to their meant purpose, Sig would be more competitive & fun.
EDIT: Oh, btw.. before anyone starts saying stuff like: "ohh Sig doesn't need this or that, its just you, blah blah.." Before anyone starts up with that, let me tell you first: "Fuck you :)" I want Beastfried in SC5, & this is just my opinion, K?, k. :)
This is based on my BoguS findings from Sig plus experience vs other characters Online & Offline, against good & scrub players.
B and as advantage it should be more powerful or be followed by an extra move