Could you clarify the rules for adding skills after each round?
It says that "AFTER each game...." add a skill, which implies that the list below should show what you add after the specified match, but in the list below, it states "as above", which could refer to the line immediately before it saying that you add "1 extra skill (Max of 2 skills for T1, T2 and T3 teams still applies) on a specified player" after the round of 64. Following that trough, you'd then add a normal skill after the final.
I assume that despite the wording, the list actually shows what you add before each specified round, and "as above" refers to the team creation rules though? It makes the most sense, but I don't want to risk running in to any bad surprises from bad assumptions.
It does if you're in scoring range when holding the ball, i.e. when in stalling mode. Then you can use your turn to score, if you're able to do so. If not, it might also not have worked in the other scenario, i.e. when the other player would not have conceded.
Also, you can use the turn to try to gather as many other SPP as you can by blocking and passing.
I take my turn 6 and run the ball 1 tile from the end zone, no one else is in blitz range. I pass the turn.
Opponent starts his turn by conceding. it is during his turn, so according to your proposed rules, the game ends immediately. I don't get to score.
Allow concession only during your own turn. If you concede during the opponent's turn, the opponent can still finish his turn before the concession comes into effect (as if you had conceded at the beginning of your next turn).
Probably easier to implement and also doesn't grant you extra spp for something that only potentially happens, just because you have the ball.
Also, if your opponent disconnects during your turn, you should be allowed to finish your turn after the disconnection timer times out.
Doesn't fix the problem. Scoring very often includes stalling, aka giving the opponent several turns to concede in time anyway.
People usually concede when they've suffered severe setbacks and the opponent can just walk the ball straight into the end zone. Often, that means that a ball carrier has managed to get past the opponents line and out of range of any players trying to stop him. If the game were to continue, it would be a guaranteed touchdown.
Sometimes it's done because it means the conceder knows/thinks he can't win anymore, but it is also often done to deny the winner a vital level up, as a final FU to the opponent.
Getting conceded to does give you extra gold and an extra MVP, but random SPP going on a skink, skeleton or zombie doesn't compensate for getting it on the Saurus, Tomb Gaurdian or Flesh Golem that you've managed to pick up/hand off to.
Targeted SPP means a lot more than random SPP, but at the same time, a concede means that you lose the opportunity for future random SPP from various blocks and passes etc, so the extra MVP should not go away.
Therefore, I suggest that if the opponent concedes, the player currently holding the ball should get 3 SPP for a touchdown in addition to the current rewards handed out for a conceded game. Obviously, this should not apply if it's the conceding player that is holding the ball, only if it's in the hands of the winning team.
You want to increase diversity by giving 8 specific races an extra slot? That has exactly the opposite effect, decreasing diversity by focusing the players into that third of the available teams, unless you specifically select the least played races rather than cycling trough. Doing so would be even worse, it would SIGNIFICANTLY lower the player and team quality in the playoffs, making it less interesting.