The "start smaller", "mvp" philosophy is good, but be careful with your users/customers.
You have to consider not only the product/feature fit but also the market you're selling into.
MVP typically has a higher chance of success in nascent markets with low competition which gives users extremely low facility to compare your product with existing products. MVP will fail if you apply it to enter a market with massive competition as users will have plenty to compare your product with, which is what happened in your case.
You have two choices, one is to enter a crowded market and go with all guns blazing - tons of features, cross-platform availability, incredible design with great UI/UX, hidden easter eggs (emotional UX), massive amounts of marketing, extreme levels of support with hands-on training, hype, offers, discounts, sales funnels etc etc etc. The other, is to find a completely new niche inside the education market where you have absolutely zero competition and where users have absolutely nothing to compare to - THIS is where the MVP/"Start Smaller" strategy will work.
I can say that because I was there trying features and getting the same "I need this, and that" you're talking about. But honestly, it should be "I'm giving you only this." and they should tell you "Where do I send my money?". I'm exaggerating a little bit.. but not that much.
The key about that is to not worry much about it: things are not as bad as they seem, and they are not as good as they seem.
If someone tells you "I'd like this feature, why don't you have it?", probably what you don't realize there is that this person is currently talking to you and is talking about your product. That's a lot. Starting from there you can go further like for example start to charm him/her.
I know. My wife is one.
Btw, a doctor friend told me he knew of an older doctor who simply retired because he didn't want to be forced to learn to use the new electronic charts. So learning internet/computer is a challenge even for well educated people also...
You did something really hard which is much easier spoken about than done (showing a product you know isn't perfect) and you successfully obtained direct customer feedback. The missing feature reports could save you a massive amount of effort by directing your energies to the right features.
Personally I'd really enjoy delivering the follow up release including a feature a customer requested. Its a great chance to hook a product evangelist because you have listened and responded to what they said.
Its possible you would have spent months building things only to discover later you built the wrong things.
* talk to potential customers
* do it!
* PROFIT
Whereas unless you are an expert yourself in the domain you're entering, it's almost hopeless.
People/businesses don't know what they want, until it's presented to them on a golden platter and all of their colleagues/competitors are already braying about it.