The only reason why a co-founder makes sense is if you are looking to give away sweat equity in lieu of salary.

The business proposition and founder track record matter more than the size of the team. Even worse, a large team has the risk to be perceived as window dressing if not much has been accomplished thus far.

You will inevitably need to find sweat equity partners as it is increasingly difficult to get financing at interesting valuations if you don't have a working product or some indications from the market that your business model works.

If you have an interesting proposition, you should not have issues in finding people that are willing to work for free in exchange for a piece of the action (or funding without having a large team).

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