I second Nicholas' response!
I think it is ideal to eventually have a true matching set of Christ and the Theotokos. That said...it's my opinion
! We have fairly detailed rules about how to organize iconography in a temple...not so much for personal use. There are long established traditions (IC XC & MP ΘV matched set, not placing icons higher on the wall than those, always having a patron saint icon, etc.) and I would respect them, but personal prayer is just that...personal.
If you create an icon corner that is condusive to your prayer...then great! That's the goal. To manifest the heavenly Kingdom in a way that makes us focus on that mystical reality. Don't let the little details and little-t traditions get in the way of that (I say this as someone who loves having those traditions and tries to stick to them quite strictly in my own personal prayer life).
As far as continuing a relationship with St. Kevin. Go for it! He's an Orthodox saint, and he shares your name...double whammy! I, as a Protestant convert, was encouraged to find a patron who shared my name. I know Roman Catholic converts at my parish who were not so encouraged (by the same priest who baptized me) and some kept their old patron, if he/she was also an Orthodox saint, or found others that may or may not share their given name. There are also many Protestant converts at my parish who had saint names as given names and yet picked a patron that did not share their name.
In short...if you aren't sure, pray for a patron and research the lives of the saints. Ask others (including your priest) about possible patron saints, how they found theirs if they are an adult convert, etc. In time, you will find the right one.
Of course, this also doesn't mean you can't have a devotion to other saints! I love my patron, but I have a strong devotion to several saints who I love very much. Nothing wrong with that. I assume, coming from a Catholic background, that's nothing new to you.
I also particularly second Nicholas' suggestion to speak with your priest about a prayer rule...and find one you'll actually do day in and day out, and that can grow over time as you grow. And, of course, praying will probably always be a struggle, at least sometimes. I don't believe I've ever spoken with someone who, at no point, felt like their daily rule was kind of a burden. I've felt that way! But, it's also a great joy.