Who are your users? Are they on mobile? Are they using a tablet or a laptop? Are they private or business consumers? There is not enough information to answer

Who are your users? Are they on mobile? Are they using a tablet or a laptop? Are they private or business consumers? There is not enough information to answer this question. Build for where your users are and build where you can get it done the fastest. Have you talked to your target users? If not, do so before you build anything. Don't pitch but talk about the problem space your idea is in. This isn't guarantee for success but you will get a better understanding. Regarding project complexity: Make it as little complex as possible but as much as needed. An MVP should solve exactly one problem. It doesn't need to be fancy, but it should look okay. But again, lot of this depends on the field you are in, your target customers/audience and so on.