-not allowing people into your house is not all that uncommon; one breede that I consider a mentor practices a completely closed aviary, and neither I nor anyone I know has seen his house but I have four birds from him, all have been in excellent health both in obvious ways and they have been disease tested and have come back clean. Also, since the breeder is a woman, let's take into account that in this day and age, novitiate strangers into your home is a recipe for disaster, and it is safer to meet in public. Also, there may have been a viral outbreak that causes the breeder to not risk other people coming into her aviary. T should have been discussed ahead of time, but by itself that is not a reason for alarm.
-no band is not ideal for some, but some breeders feel they are more risk than they are worth. Since the bird is already in the USA, it should not cause a problem. If needed, you can buy a rolled stainless steel open band and have it applied by a vet. Also, right now I am raising four cockatiels; three are banded, one is not. The non banded bird happened to hit her window for banding BEFORE her older sister and during a major crises at home. I missed it. It is a bit embarrassing for me, but in the long run not that big of a deal unless the new home wants to breed her with another bird from me down the line and needs to insure that the birds are not related (although to be honest by her mutation I couldn't possibly mess up remembering who she is related to in my small flock).
-bad people skills, we'll... Tacky, but not necessarily evil.
-unprofessional online presence is the same; annoying, but she may still do an amazing job with the birds, she just isn't great with the business side.
All that said, I wouldn't buy from a breeder I didn't already know unless I am allowed to see the conditions they were raised in and lay eyes on the parents (yeah, I'm that girl who doesn't think it is ok to have plucked breeders, feed all seed to breeders, keep them in tiny cages with no toys, etc, and I'm not paying you to do that). In addition, if you don't see thei parents, there is no guarantee the person actually bred the baby, and while I don't have a problem buying from a professional hand raiser if I choose that, I don't want to buy from a liar who SAYS they are a breeder if they are not.