Encouragements aren't required to get people to post in this forum, that's for sure.
I think the changes are good else I wouldn't make them, if you don't feels as special anymore when everyone can have an avatar, that's a shame

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Lots of people have requested the changes. Smaller avatars than 100 pixels are useless in my opinion, you can hardly make out what they are.
I'm doing the changes I feel are best for the forum and for the members to feel welcome. We could have a few million members with 100x100 avatars without worrying about server space, and loading times are hardly affected.