slackergod: Not sure, I'd have to make a script for it to see. My hunch is that Yoshi's dodge and faster stun would favor him, maybe something like 60-40?
Guigas026: Rank points gained and loss depend on who you're playing -- you'll win more /lose less playing higher rank, and lose more / win less playing lower rank. (You'll also lose less just for being under SR29.)
runerocker864: Insignia doesn't work that way -- Insignia damage is only added on after other effects like critical hits have been accounted for. thus, Slingshotting with Insignia is only 64, NOT 72. Insignia is still not awful on Popo, as it significantly improves the damage output of Knee Bash and moderately increases PD, and also lets Herbap Prep buffs proc on CC, Amaya, or Cain. (DP and Feather are still going to be better picks generally speaking though.)
spazyspaz: Slingshot is almost always better than Poison Dart for Popo. Slingshot averages 32 damage, PD averages 22.6. Slingshot hits for big damage 50% of the time, PD only 45%. Not that PD is without its uses - it starts looking better paired with Deadly Poison since hot rate becomes more important, and it can also be used at both ranges for less energy cost. And of course, Oni is immune to crits.
GodsEyes: You'd be better off using Staff Strike in that deck. A crit buff on Popo's Slingshot raises the crit chance from 50% to 60%, whereas a SS buff raises the crit damage from 60 to 72 -- and 72 is a key number, enough to kill a 70hp, 2 phy resist character in one shot.
Honestly, if the game gets boring for you because there aren't enough cards, I think you need to start asking more from your game-playing experiences in general. Challenge yourself - learn the game inside and out, and get good at it. Get into the top 100, Compete in the league, etc.
DamageDone: Well, it becomes easier to just link a page with the answer to something people ask/comment on all the time, especially considering the page probably answers some of their other questions as well. I generally watch any of the wikia articles I link and fix them if modified incorrectly, though obviously I haven't fixed up the entire wiki (your example no longer recommends Helene now though =).
Jinndukken: Not so much, no. It's not perfect, but the balance is good overall; there is only one garbage tier character (Helene) and while some are a little overpowered none break the game or anything.
Kark: The over-arching point is that cards aren't the most important part of the game - player skill is. Yes, ValkAnex and JujuFeather are clearly too strong. But the game is balanced well enough overall that it really isn't that big of a deal - the tiers are pretty tightly packed. It could certainly be better, no arguments there - but what we have now is not bad.
Redsnake: Assuming Popo had Feather equipped, that's about a 13% chance - not really that unlikely. In addition, using Helene is not a good choice if your goal is to win.
Another reminded for the league - Skill Rank 25 or higher is required. See http://www.kongregate.com/forums/1/topics/53844 for information. Signups will be ending (and the league) starting fairly soon, probably about 2 weeks or so.
Karkadinn: Yeah, that's just not true. There's only one non-viable character right now (poor Helene, so awful). I've seen people pull top 5 ranks by using the likes of Andromeda, Cain, Amaya, and Popo. There ARE balance issues, no one can deny that, but they are often overblown; even in its current state the game is pretty well balanced overall.
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