I'm currently considering either a time or difficulty based solution

Time based: X coins generated per hour. Coins are effectively distributed by the percentage of hash power you contribute to the network. Subsidy reduction not necessary.

Difficulty based: Amount of coins generated scales relative to difficulty. Amount of coins generated per MHash remains flat, no matter how many miners are on the network. Subsidy reduction would be in accordance with Moore's Law.

I believe both of these address a lot of the problems recent altcoins have had with their launches, although the difficulty based solution is far more easier to implement that the time based one.

There's nothing to prevent what people choose to do with their coin. But, by design, there won't be the "early miners with a ton of coins" scenario that we've seen play out multiple times, so people won't have tons of easily acquired coins that they could just dump.