The limits on AAISP are designed to be enough for mainstream use, and easily enough, I guess the few guys replying here are not mainstream users, and my view on that is then yes AAISP is not suitable for you guys.
AAISP is a small isp and allowing unlimited usage could completely trash their network, so I can understand their approach. 2.4tb is absolutely huge usage even though it may not seem like it. Note though office::1 package does cater for that. So there is an option on AAISP even for that level of usage.
I wouldn't say mainstream users though, as mainstream users would just use a mainstream ISP.
AAISP are a very specific middle-ground for users where reliability is more important.
I do find their approach a little odd though, as surely having a quota doesn't reduce their peak-time load, and its THAT load which determines their overall network capacity.
I preferred how Plusnet used to work, where the quota would apply to peak-time usage and you'd be throttled at peak time if you went over. Its a lot less drastic than having to pay for excess usage. Kinda ironic considering I had just been talking about how much I hate packet filtering by ISPs, but I hate quotas more.