Hey, I actually played the original collector a while ago, it just never got around to deliver some feedback, so even with the competition really close now
here I am taking a few minutes off, hope it helps anyway.
First of all, I like the non-violent gameplay and basic idea behind the game - team based games can be pretty rad.
But, I did not have much fun with it actually for the following reasons:
The gameplay is too random. Due to the random nature of the level and placement of the stamps it's really not possible to come up with a strategy so the game ends with everyone running around frenetically trying to get to the nearest stamp or just running around aimlessly, because the nearest one has just been snatched away under your nose. It's kind of like watching 8 year olds play football (the European definition) - everyone is just running after the ball.
This might be intentional, but I don't feel like it works (for any kind of game actually), because all it boils down to is who sees a stamp appear somewhere and who is the closest to it at that point. If you have a full team of human players you can obviously divide the map into sections with every player handling one of those (to get some control over the others), but I doubt that would work out for very long.
So what I would suggest is toning down the randomness of the game (not just in terms of the map, I will get to that later).
If you were to keep the basic structure and idea you have now, you could make the stamps appear in pre-determined locations and either add something which teleports all players too close to this location away on appearance of the stamp - to discourage camping, but this could also lead to some frustration OR just always use the location(s) with the lowest player density OR something else, I actually don't really think this would work out very well in any case.
Another suggestion would be to change the gametype to be more capture-the-flag based (like in TF2 or something similar, just without the killing).
And yet another suggestion (though this one requires many structural changes) would be to change to something attack-defend themed where one team gets some time to set up a defence for the stamps (like moving around ladders, adding barricades, teleporters, etc.) and maybe even move around the locations of the stamps and after the time runs up has to keep the other team (which spawns on one end of the map) from getting to the stamps and then actually getting out with them again (being kicked will make you drop the stamp you are holding, you can only hold one at a time).
Well these are just some ideas, which I feel might be too drastic, but the gist is I suggest you change the gameplay somewhat to encourage more strategy and make the game less random and luck based.
The move-set of the player feels good, I actually like the ladders, they work really well in this game (as I mentioned before this is not a common thing for me to say), even the fall-damage feels fair, though the kick could use some work.
At the moment with the player not being able to move while kicking it is kind of useless as you can hardly use it "in action" (run up to a player or try to stop someone running away from you), except when someone tries to go up a ladder without jumping on it (which is a rather stupid thing to do). When standing still people can just jump over you and the hit detection feels really narrow, so it's hard to connect anyway.
So what I would suggest is making the player able to kick while running, but to discourage just running around kicking like a mad man, either add a cooldown to the kick or make it or slide-kick (so the player actually slides forward with high-speed while kicking everything in his path - similar to the "falcon kick" by Captain Falcon in Super Smash Brothers).
Also besides that, adding a sprinting ability immediately improves almost every game
As much as random level creation adds replay-ability I am kind of glad you are ditching it for this version, because in my eyes it just created several problems.
It just adds to the lack of strategical-bility (I am making that a word!): Teleporters would set you in mid-air, so you would take inevitable fall damage (well this is a risk-reward thing, so it might just be fair again...), some places were inaccessible, some were dead ends, some ladders were basically useless and in rare occasions you (or some other dude) could be spawned in a tiny hole in the ground without an exit.
A minor nitpick: A small help screen explaining what to do and how stamps are counted would be nice (and will always be regarded more than a readme text file).
Lastly, the graphics and music were both solid. I liked the cute little characters and 8-bit charm with it's low-frame animations, yet every frame getting across exactly what it is supposed to.
So yeah, dunno if am talking totally besides the point, but I hope you can take something away from this
Thanks for reading and I am looking forward to what you come up with for the next version (for the replay competition or otherwise)