Basically, there's two main complaints that I can see on this forum about pics:
1) People don't like having to scroll sideways
2) People on Dial Up are crippled with big pictures
To solve the first one, I'm sure there a hack on the net or one could be written to simply resize the picture to 600 wide but the whole picture would have to be read.
To solve the second one, write code to get the file size of the picture. If it's over a certain size, eg 20K, don't display it. If it is less than 20K but bigger than 600 wide, the first bit of code should fix it.
As for pictures being displayed in Quotes, just disable tags in quotes. Or just allow one previous message to be quoted eg:
I agree
Instead of:
lol
OMG
I agree
Automated Image Resizers for IPB2
http://www.mods.invisionize.com/db/index.php?f=4552
http://www.mods.invisionize.com/db/index.php?f=4445
Reckon the first one is the way to go.