I had a wonderful feeling when my first level Strongheart Halfling Wizard in an in-person game I DMed grew up and was eventually able to cast level 9 spells due to level increases. The campaign lasted about 16 months.
After that, though, I got tired of low levels and just wanted to start around level 7, where things got good for Wizards (and a lot of other people), but my group wasn't normally up to that level of tracking things. We tried a variety of games starting at a variety of levels, but our most successful games/campaigns after the initial Xeen campaign were
Red Hand of Doom (L5-L10) and
The Metaphysical Revolution (L1-L3).
Play-by-Post-wise, I started a game with SirPercival at L1, but that was to prove I could solo the game. (Go, go Dragonborn Warforged Conjurer1 with Mercantile Background who sells most his cantrips and invests heavily in Magebred animals!) Other online games I've played often started above level 1, but rarely did we level.