You may end up with a provider that doesn't give you any feedback on how your service is being received by the public. You may end up with a provider that can't handle the load that you generate. You may end up with a provider that doesn't offer an intuitivly navigatible server. If you have to change providers in mid-stream that can cost even more money. I didn't think to add domain name management to the alternative services, which I should have.
Service providers can also offer gopher access, autoresponse email, and anonymous ftp.
As far as I am concerned for a good net.presence you should have as your minimum, basic WWW server, autoresponse email and a local email account. A personal domain name so that you can get name recognition is a very good idea, especially now that everyone is going bonkers and registering product names as well as corporate names. If you don't have the time or inclination to make good web pages, this task should be farmed out. If you space out your announcements and get feedback from the provider about how many contacts you received from the last announcement, you can tell where your potentially interested parties are at and plan future announcements accordingly. Netcom currently only offers ftp style access for web pages.