There is a split in opinion on whether stat caps are good or bad. It is probably safe to conclude that playtime is the primary source of the bias, with the casual players preferring stat caps, and the hardcore preferring the perpetual carrot of stat advantage. I propose a compromise:
Stat caps could be implemented on a per-character basis, and dependent on the age of that character; the older the character, the higher the stat caps. This would not be based on playtime, however it would be based on date of character creation. There is a key catch, however, which makes this suggestion relevant to the title: IP addresses with multiple characters would share their aging time. In other words, a player that creates 3 alts in addition to their main, would have stat caps at 25% of what they would be for a character made on the same day, with no alts.