Do you have a relationship with a CU? They would offer you a better chance of fixing it. The personal loan will be rough, sometimes they report negative on your CR as a Consumer Finance, then your hoping to refinance which isn't a guarantee...best bet is with a CU you have a relationship with or even a local bank, someone you can sit down with face to face. OFC everything might work out just the way you stated (planning) however, its not a sure thing and could backfire on you with the personal loan. This ofc is my opinion and not gospel by no means. Good luck in trying to get it under control.
There would be pros and cons with a loan, depending on your profile. It could help your credit mix. But overall, I am not sure it will really make a big enough difference to achieve any credit goals you may have, aside from simply seeing the number go up a bit. It may or may not help reduce your expenses, which, if I may say, seems like the real issue if you need a loan to get your balances down. I agree with the advice to talk to a credit union (join one if necessary) and ask what they suggest or what they can do to help. Good luck!
Wouldn't you need to take out a loan that is much larger than what you owe on the credit cards, pay them off, then use the remaining cash from the loan to pay down the loan principle to decrease utilization? Or are credit cards and loans Utl separate?