[jtfairbank]

Great breakdown, adding a few modifications:

1. I'd use a SAFE [0]. They are simpler than a convertible note since they don't have the debt instrument and match up with the investment intent more fully- to get equity at a future for money you put in now.

2. I wouldn't worry about the employee roles. You have different opportunity costs and can try to make them up later via bonuses etc, but I wouldn't formalize that now with an additional equity grant.

3. The most important thing here is that the split is relatively equal (50-50 as cofounders, adjusted by a few points by the investments). To make sure that both of you have an equal position in decisions and discussions, you should keep the equity gap between you as small as possible. That way there will be no weird power dynamics. Having 5% more due to your investment is fine, having 20% more is not.