I think you need at least 1 AP option. Having AD mids is fine. I just don't think you should be constrained to them. Mid is expected to be AP more than any other lane. If you only play AD mids and you're a mid main, you're going to end up with a LOT of AD-only teams.
If you're an early pick and there's options to later pick AP champs it might not be entirely your fault (but if I'm a mid/adc main can you blame me for not having an AP top or AP jungler?), but if you're a late pick and ask for mid and it gets given to you and your team goes AD and you only have AD mids, you're going to have a bad time.
I'd just suggest having at least 1 AP option. Give yourself a chance there.