Game Type: SP, MP, MP with/without AI or both?

Hi all,
to concentrate our design, I would like to read everyone's opinion on the intended game type. My understanding of the requirements and personal preference goes to a pure multiplayer game, where we can decide how many players we would allow to participate in a single game on a specific map:
1 vs 1, 2 vs 2 etc. up to 4 vs 4 with asymmetric combinations, e.g. 2 vs 4.

The other options here are: MP with play against an AI, or even a full single player campaign against AI in a set of maps.

I would not really want to go there though. For ease of development, I prefer just a pure multiplayer game, no AI enemy, no interconnected maps (campaigns) and up to a maximum of 4 vs 4 player (asymmetric) game sessions. Each game session should be targetting 30 ~ 180 minutes average playtime.

Leaderboards, persistent scores etc. are also required to make the game attractive long-term though. Not easy to make!

Firstly I belive it is important to concentrate our programing efforts fully on developing the multiplayer aspect of the game(hence no AI)

I would prefer it if we allowed a maximum of 8 players per game, giving 4 vs 4 capability. Which can be split up multiple ways.

I think its best if we keep multiplayer aspect purely human, ie no AI whatsoever. This should be our main goal.

However it would be nice, eventualy to have the option of running a linear single player campagin to introduce new players to the game.

I would have to agree, get the game up and running with the lack of AI, but then come back and revsit it as a later up grade.