...this is part of a development process that is something to look out for on the next one.
Yep, that's the ticket. Initially I think it's better not to work overlong on each piece correcting and revising; you do have to have the gumption to do some but it's easy to take it too far. Finish and move on to the next, down the line each of your training sculpts is then a concrete example of the improvement you've made.
Being right handed I find left eyes more difficult than right ones and always have to check several times for alignment and size.
One side is always more difficult but do you mean the model's left eye or the one on your left? I find the head's right eye more difficult, partly because the nose simply gets in the way.
One tip I got years ago from another member in relation to painting eyes was to do the difficult one first, then it's much easier to get the easier one to match that. This has been even more helpful when it came to sculpting eyes, especially at larger sizes.
But it is true that every person has two different faces half.
This is true and it can be used somewhat, but some sculptors rely on this a little too much
At real size the differences are often quite subtle, and these would be very slight at small scales so it's very easy to overdo it. Better to strive for the ability to create perfect symmetry - as they do in academic sculpting training - so you can achieve that when desired. You can always
choose to tweak a feature here or there for interest (rather than it being forced upon you).
Einion