I was advising a friend on this recently (he being a high-skilled engineer, looking for a non-technical cofounder) and IMHO one of the biggest items that either

I was advising a friend on this recently (he being a high-skilled engineer, looking for a non-technical cofounder) and IMHO one of the biggest items that either side should be looking for is startup experience. If you're a skilled "x", you should look for a skilled "y" that is at your level or above, and does not need to be taught the absolute basics. Getting any project off the ground with a cofounder that has never worked in an entrepreneurial environment is going to be extremly challenging. The bigger your skills/assets you're bringing to the table, the more you should be filtering for experience.