Cofounders are indeed critical to success. Don't feel tempted to compromise just because you are in a hurry (same as marriage!).

Also, you should plan for bad outcomes like a founder who doesn't fit in, can't fit in, etc. and ensure you haven't signed away a load of equity, which will make you want to keep them on board! Take legal advice on a good balance between attracting good talent and not risking the company equity in the process.