Hetero-female/mid forties/married for over 20 years. I play as any gender/sexuality. Generally start out with a female PC who romances a male. I don't do true self inserts, but my first play through will have a handful of similar traits. For the most part, I
do try and incorporate
some aspect of myself, in every play through. This just helps me, with immersion. But it is usually something small, simple. Not uncommon for it to be related to either the friendship or romance paths, that are available to me (though I eventually try nearly all of the romances).
It is interesting to read that some have a problem playing a PC of the opposite gender of themselves, when there are VO involved. For myself, I found it
easier to RP a man, with a voice over. An example, in DAO, I had quite a few less male PC's, than I did for DA2 and the ME series (it was almost split down the middle - females edging out the men by a hair).
I have never completed a romance for Leliana or Merrill. Started them, but never completed. Watched the rest on YouTube.
And last confession, like others have admitted, I too have gotten "hung-up" on one or two characters, so my number of play throughs with them as an LI,
can be staggering.

Zevran in DAO, Fenris in DA2, Thane in ME2. But, that still didn't stop me from trying the other romances (and often enjoying them). So.....going by history, if I was to just "guess" who I might fall into that trap with, I would say possibly Solas, Dorian and/or Cassandra. Once meeting all of them in-game, that might not even be close to the reality of it: maybe it will be Josephine, Blackwall and Sera. *shrug*