Guildleves create a barrier to new players
I recently rejoined the game and feel the game has made good progress over the past year. That said the current Guildleve system creates a huge barrier to actually playing the game with everything in its current state. I've been able to hit 24 on one character and at this point I'm effectively stuck. Guildleves really seem the single best SP source in the game, but you are available in such limited quantity that you can't level on them alone. This leaves behests, party grinding, or solo grinding. Behests and party grinding are great, but with the population in the game at it's current state they aren't really viable at this level. I don't think anybody wants to sit and shout in town for hours trying to get a party invite. It ruins the fun of the game. Behests also could be fun, but at this level it's rare to ever see another player doing them. That makes doing appropriate level ones difficult. So that leaves solo grinding which is neither fun, nor efficient at leveling.
So my feeling is that the timer on guildleves should be shortened to 1-2hrs, or completely removed with random leves being accessible whenever you exchange a completed one. The rewards can be almost completely removed and it wouldn't matter so long as the level experience is improved. This is almost necessary to keep new players coming into the game since it will continue to be difficult to find parties to grind out SP at these levels. The server populations just don't seem to be large enough to support that kind of play style.