[Opinions] Re: Jenna Vs. Jennifer
I think Jayne nicknamed Jenny is a great arrangement. I love Jane (and Jayne is a variant I like well enough) and I've always thought Jenny was a very sweet, earthy name, or nickname in your case. I like Jennifer quite a bit more than Jenna, which sounds kind of whiny to me, but overall would greatly prefer your name situation as is.
On the topic of Jennifer, I feel like I'm one of the last people who finds it to be a genuinely pretty name. Same with Heather, which I think is very appealing if you can look at it for what it is and not get mired in any particular decade.