Ambition? No. As Zarx explained, the financial risk carried with an AAA title means that most of those games are automatically less ambitious as they pander to sensibilities which a publisher knows will do well. Whereas an 'indie' game can do whatever the hell they want, mostly.
Production values? Absolutely. Retail games nearly across the board have better quality assets etc. than indie games, bar a few exceptions like say, Star Citizen. There are a few 'indie' games out there that could go toe-to-toe with lower tier retail titles, for example I think Hover: Revolt of Gamers looks very good.
Depth and length? I think that's debatable. These factors aren't in any way tied to production values, so I believe you can get as much content (if not more) out of certain indie games than you could out of your average retail release. It just depends on the game. Something like Thomas Was Alone obviously has less content than Terraria. But there are plenty of indie games out there with a wealth of content.
I think you address an important point with some of your replies in this thread though. Downloadable title =/= indie. Something like Resogun; Super Stardust Delta; Journey; Rime etc. are titles which don't see retail release, but are very much not indie games. They're funded by a publisher (in this case, Sony) and I have no doubt they have pretty sizeable development budgets behind them.
