Great analysis. On Enterprise SaaS, my experience running Buzzient for 7 years as a bootstrapped/angel funded SaaS company revealed the following:

• Enterprise SaaS has a longer J-curve on a per/account and per company basis, due to extended decision cycle for enterprise solutions. This makes it harder to bootstrap since you’re cash flow negative for a longer period of time
• Enterprise SaaS really has at least two categories: Edge and Core. Edge SaaS solutions are not dissimilar from SMB SaaS; I’d posit that most of the SaaS solutions marketing themselves as Enterprise today are selling at the Edge of the network, departmental applications which don’t require CIO approval or access to full enterprise assets (think digital marketing solutions). Core solutions, those leveraging the enterprise CRM, HCM, ERP are a lot harder to sell/deploy and in this case bootstrapped companies are competing with entrenched Enterprise SW vendors making the transition to SaaS. Again, this requires deeper pockets and a longer time horizon.

I do agree that we’re going to see more bootstrapped Enterprise SaaS companies, thought I think most will be very vertically focused.