I flew EVA RL + 2 Y seats in July

RL is not children-friendly at all, there's a mom and 3 year old in front (so 10G, 10K) of my seat (11K, last row of RL) and the mom kept getting up and going over to the girl's side almost for the entire flight as she was coughing a lot

We trid the swap, hoping that people can sleep better in the flat-bed
My wife tried to slept with my 2.5 old girl in the RL seat, didn't sleep very well as it's not wide enough for 1 Adult + 1 15kg girl
In the end, my daughter slept the best while the 2 adults suffered

I think we would've been better in a 3-seater Y seats in the back, and let the kid lie down between 2 adults

Keep in mind - ELITE seats' armchairs do NOT raise up, so kids cannot lie down on a 2-seater.
If you're flying low season, I'd much prefer having an empty 3-seater (book window & aisle, hope for empty middle seat) than 2 Elite seats

You could also book 1 RL (11K) and 2 1st row Elite seats (20H,K) so it's only 1 curtain away