I think the rule of thumb is that if you want the audience to remember something, you show it to them three times. So three "hints" to her underlying character may be a good place to start. ^^ But I agree, it can be a delicate balance. You want her to be defensive with Vin of course, but you don't want her to be defensive toward the reader. XP
And no problem. I'm glad I could be of some help. ^^ Some people don't always appreciate honest constructive criticism, but I personally think that every writer, no matter how good, has room to improve. You can always try asking people specific questions when asking for critique - such as if a certain scene works, or how the pacing feels, what was their least favorite part, if the imagery works, if any parts are confusing or dull etc. Sometimes when just asking for feedback in general you don't get the answers that are going to help you the most. If there's a part you don't feel is working, but can't figure out why, that's a good thing to point out when asking for some critique. And of course, you may get different answers depending on who you're asking - a writer's opinion may be different from a reader's opinion, which will be different from an editor's opinion.