As you know, HAM mode always synthesizes two pixels, by either
a) reading directly from a color register or
b) by replacing a color component from the previous pixel.
Therefore it is easy to implement a slightly enhanced HAM mode which interpolates the first of the two pixels in case b).
In this picture, the difference gets visible to some extend:

However, for most pictures I tested, the result is hardly visible with the human eye, so it might not worth to offer it as an option. It's easy to implement though (just a few lines of code) ...
Oh boy, the haircut is so eigthees. 馃
I think the crop of the enhanced HAM is definitly smoother.
If it is easy and the code will not get messed up then I would do it, simply because the other emulators don't have it. vAmiga will be a little bit better in displaying HAM 馃挭 than the big emulators out there. But pssst, 馃檴 better don't tell anybody that vAmiga is superior in this ...
But yes in the big picture it is hardly visible ...
EDIT: is the princess in defender of the crown in HAM mode? This would be of course the killer argument to implement it, a no brainer then 馃槀...
If you wish to see a real haircut from the eighties, you just have to click to the next picture 馃槀:

Actually, this picture is a good examples how barely visible the enhanced HAM mode is. It's hardly impossible to distinguish both versions if they are drawn in normal size.
Yep definitly the 80ties, look at this freaky hairs. Maybe punk style? The crop is a bit more blurred. Can鈥榯 tell wether it is better in terms of quality though. Pretty close. Big picture seems to be identical. Whether to implement enhanced HAM or not I am neutral.
I bet this person is now already 60 years old. Maybe still the same hair cut, no? 馃き