The ETA thing might be something they could implement, but I think you just open yourself up to a lot of complaining if the info isn't exactly right. It could create new problems because people will try to time it more.
WiFi is a non factor to me and not a bus issue. Covered bus stops need to happen, but more of an infrastructure issue, not exactly a problem with how buses operate. ECV is about as quick as it will ever be unless they start doing ECV buses, which I think could work with some creativity.
The other things you mention I don't see as major issues. I think they have good bus only lanes and I think the the waiting for a bus issue is minimal. I never feel like I'm waiting too long for a bus, honestly. I think we are just in disagreement on how well the system current works. The only issue I have is how crowded they are and kind of unpredictable on timing. They solved it with express, but I don't think that solution is possible on a mass scale because you have inherent problems when moving a lot of people.
No WAY you can say their bus service "sucks" compared to major cities. I live in a top 5 city and the bus service is a total joke, no comparison to Disney. I don't just say that anecdotally either. I used the bus service for years communting downtown to work and it's AWFUL. I remember thinking I wish Disney ran this service.
I've used subways in NYC, Boston, and extensively used public transport in DC...all are a joke. The only public transport that's been good in my experience is overseas.