Just curious, what about smaller rounds? Let's say 100k, how do you balance out legal costs that approach the size of the round?

Your legal costs shouldn't approach 100k in a seed round! 3-5k ...find a different attorney.

Yep. Series seed can be done for under 5k, and so can convertible equity/notes. It's less about the type of tool you're using, and more to do with how much modification to the standards you want to do. Thats the beauty of standardized documentation, minimal negotiation and cost.