Hey,
It seems like the Sabrewulf board is picking up, which is great!
I need help on what my best options are after my juggles or knockdowns. I tend to go to Overpower or mk, but obviously those are not good options for all cast.
What are the best options to keep pressure on wakeup? More specifically for Cinder - not sure why but I really struggle against him.
Also, what is required to take the potential damage when you end your juggle (cash out your juggle damage)?
Depending whether the opponent has a DP or not set them up with a high or low attack… You can only block one or the other…
One thing to keep in mind is doing nothing on your opponent’s wakeup is just as important as hitting a button. When they recognize that you are patient enough to wait for them to make a mistake, they will be afraid to hit buttons themselves. This then opens up the path for you to be aggressive. I generally would say 50/50 - aggression/patience on their wakeup is a good mix. Of course that varies depending on the wakeup options that particular character has.
Cinder in particular definitely can not be pressured a majority of the time. Usually I will let him dp and then punish. Even the fired up version is more punishable now. Once you’ve established a slower game speed, start mixing in throw attempts, dash mixups and more blocking. You just have to be patient against him.
I generally treat Glacius the same way. A wakeup puddle punch beats any button we have. So I wait for it and then punish. A big tip against Glacius is to throw out c.HP in neutral. It low profiles lance, interrupts shatter AND gives you a (more or less) safe jump. Knock down, immediately jump forward with HK. It will beat out most of his options but you land in time to block puddle punch, or shadow puddle punch.
As was mentioned, characters with good DPs (Jago, Orchid, and now Thunder, etc.) have to be respected for the most part, but they are still susceptible to dash->mk or dash->c.mp openers if you’ve got them trained. Overpower is also good against Jago. Knock him down, take a small step back to be out of DP range (they won’t notice it), and charge up overpower until they either whiff the dp, or block. Fully charged it’s unblockable, so you might catch 'em looking. That’s always fun. 
I use c.mk to bully some characters without meter like Spinal or Maya.
c.HP is useful against Aganos because it ignores armor and gives you another hard knockdown. At near-max range it is unpunishable by him on block (I think) so it is a good fishing tool against him. Standing HK is also a good one on his wake up. It ignores armor and combos into just about anything you want. Its startup is super slow so you have to hit the button earlier than you would any other in order to time it properly with his wakeup. Of course when he doesn’t have chunks, just go crazy on him. Unfortunately, season 3 Aganos ALWAYS seems to have chunks.
Characters with decent back-dashes that aren’t afraid to use them will get punished with a heavy ragged edge opener on their next wake up. I find myself having to do this against other Wulfs (wulves?) more than any other character.
Again, patience is key against all characters. In this game everyone has a multitude of things they can do on wakeup and anything you do after scoring a knockdown can usually be countered in one way or another. So you have to mix up hitting buttons and hitting down back to make your opponent scared.
Dash-through meaty button is still a pretty solid option. Mix it up with dash-through->throw or double dash throughs. Keep them guessing.
Meaty throw, meaty c.MP TC, meaty overpower, meaty s.HK and dash through meaty c.MP TC or meaty throw are all amazing options that are very hard to try and react to.
Meaty leaping slash will also work if you don’t spam it.
Meaty s.MK for solid meaty pressure, since it gives you confirmable follow ups on block and on hit.
Late neutral jump is also good once they’ve started fearing your oki. You can either j.HK or divekick crossup > c.LP TC.
Like @TwoDogKnight stated, you also need to practice patience. Bait out the reversals with a block outside of grab range or a well timed backdash. Vs chars with good DPs you really need to make them afraid of using the DP, by correctly baiting it, and also as importantly, by punishing it accordingly. Don’t throw punish DPs, and don’t punish starting with lights. Overpower > shadow opener would be the preferable punish, but if you don’t have the meter to spare, overpower > light ragged edge.
As for cashing out, only ways to cash out a juggle are either with recap > grounded ender, or directly with shadow eclipse.
Cr.LK or throw on their wakeup. If you’re facing the likes of cinder, Thunder and other similar, you have to safe jump (After a hard knockdown, you do a jump in HK, If cinder blocks you are at an advantage, If cinder DP on wakeup, you will block it).
If the opponent has a true DP such as Jago, Orchid, Fulgore, You have to respect it and make the read on if they are going to do it or not.