XF 1.5 Different avatar dimension for user group

I started to use the account upgrade feature.

For subscribers, I am interested in giving them a bigger avatar dimension as one of the perks. In the user group config, I only see the option to set avatar file size.

Is it possible to have different avatar size for a user group?
I hope they make it a built in feature.

I am kinda wary of installing third party addons. From my vBulletin experience, installing too many third party addons can make it a pain when it comes to forum upgrade.