I can't imagine any VC denying you funding because you are not a DE corp. Plus, you save ~$400 per year in Delaware Franchise Fees. Even if you are a DE corp, you'd need to file paperwork to qualify to operate in CA. You also need to pay taxes in CA, even if you are a DE corp.
If you do a search on http://kepler.sos.ca.gov/ you'll see that Google started out as a CA corp.
C2119530 09/04/1998 MERGED OUT GOOGLE TECHNOLOGY INC. DAVID C DRUMMOND
Once you get your series A/B and get big... I'm sure it's relatively easy to convert your corp to a DE corp.Since you are charging $100 / $300, you probably want to target as wide a customer base as possible. By concentrating only on DE C Corps, you are limiting yourselves to the Dropbox/AirBnB style startups. What about all the potential S-Corps / LLCs that could benefit from your service?
I run an S-Corp, and would have easily paid you $500 to get all the paperwork (correctly) filed for me in CA.