Thanks for your replies everyone.

I know this reply is a bit late!
I may consider bonding in the future if it's an option, though there seems to be quite a few negatives to bonding/veneers so I'm more inclined to just leave it natural.
DrJasonKTam wrote:My personal feeling here is that you have had some relapse of the anterior teeth and that the size of your small lateral isn't actually that small. The lateral is now tipped lingually, which makes it appear even shorter than it actually is. Much of the asymmetric appearance has to do with the length of the tooth. It looks like you did not finish with a fixed lingual retainer in the upper arch, so you have experienced some shifting. If anything, I would consider realigning the teeth, with extrusion of the laterals to better match the lengths of the centrals.
Any veneer or bonding you do is going to have the same effect of increasing the length of the tooth, not the width, since it doesn't look like you have space on either side to make the tooth wider. Also consider that once you do a restoration, you are likely committed to replacement throughout your lifetime, and that a veneer or bonding will always stain at a different rate than the rest of your teeth.
I thought it was because of the positioning also. I kept stressing that, however my orthodontist told me it's because of the size and there was nothing they could have done with the braces to change that. Prior to my braces coming off, I also raised my concerns with my dentist and he pretty much said the same thing. It could be a combination of the size being slightly smaller, and how my teeth were shifted and pushed back after extractions. My orthodontist spent many months (years actually) perfecting each and every tooth position, and this seems to be the best result possible from what I had.
Also I did have a fixed retainer to both the upper and lower arch, as well as a removable retainer. My teeth haven't shifted at all.