I understand your concern and it's absolutely your choice on who to use in the future.
Still--honestly--I'm having a difficult time getting to the point of defining that behavior as unprofessional.
Your agent should have strongly urged you to have a final walk through. The fact that she didn't is a point of concern. If we're keeping score, that's at least 1 point in the direction of "unprofessional."
But you were aware that some trash had been left behind and the Realtor even suggested that the seller set some money aside for the clean-up cost. That was the right thing to do to protect you. You declined, trusting the seller to do it. If we're keeping score, the Realtor's suggestion that the seller escrow some clean-up money is perhaps 1 point in the direction of "professional."
So the seller ran off and didn't handle the trash removal. You asked the Realtor to handle it (remember--she'd provided an earlier, better way to handle it, through escrow), and she did, paying for the trash removal out of her own pocket. That's perhaps 1 more point in the direction of "professional."
However, once you got in there, you discovered that the clean-up was incomplete. The Realtor apparently had had some of the work done, but not to your satisfaction. And, frankly, it doesn't sound like it'd be to most people's satisfaction. If she'd committed to doing it, then she should have done it properly. That's 1 point in the direction of "unprofessional."
I agree: The situation could have been handled better. And, as I said above, it's your choice on who you choose to help you sell the property.
There are really two questions involved here. The first is whether this agent will do a good job for you. She knows the area; she's a power in the area. That counts for a lot. Still, you say that you don't think she's the best you could get. So, determine--as objectively as possible--where she does rank as far as agents who "control" that market and could help you sell your home.
The second question is: Even if she is objectively the best agent, can you accept her earlier dealings in the prior transaction? Can you look past them, from a personal level? And there's no right or wrong answer here. I'm not suggesting you ignore how the previous transaction was handled. If you feel that that'd be a major impediment, then even if she is objectively the best, you might well be better off choosing someone else.
So, unfortunately, I'm not offering a clear-cut "yes, use her again" or "no, don't use her." But I hope I've raised some issues for you to consider as you make that decision.