To release at the right time is really an art! Some considerations,
1. Hype in the crypto markets; primarily, hype surrounding Bitcoin and the hype surrounding Bitcoin 2.0 products like NXT, CounterParty, etc. For instance, atm NXT is all the rage, and a product competing with it - if sufficiently impressive looking - might steal some of that 100 million market cap.
1.1. Topical Type hype, such as privacy, nationcoins, etc. For instance, we had a stretch were DARK, X11, Anoncoin, etcetc. were all the rage, and a stretch were Aurora, Mazacoin, Maltacoin, Electronic Goulden, and all the rest of the nation coins were trending.
1.2. Event-hype over events like elections, as fuznuts mentions can be exploited for Voting DACs, or the Olympics, that Dogecoin exploited to do the marketing stunt, and Football VM coming up will be exploited in betting/prediction markets, etc..
2. Space them out (but not too far apart!) AND list them in a giant visual plan AND fulfill each expectation, that is how to build investor confidence and trust that you know what you are doing. In addition, this will create a fun game for the speculators who love the kind of dynamic market it will create.
3. As davidpbrown and others point out, release the products you are most comfortable with first, as the hype for the latter products will depend on the successes and the attention created by the previous products. If the first and second releases fail to gather attention, it will be more difficult to market the third, and so on.
BTW, there is no need to release the exact release date of the DAC when releasing the date of the snapshot. The snapshots should be announced fairly soon in my opinion, because otherwise we are not free to launch when it is optimal to do so, on command. (imagine having Auroracoin 2.0 ready to go just when Auroracoin was was going crazy, versus having it two weeks later - it is all the difference in the world.)
When doing snapshots, I think the main consideration is the influx of money into BTC, and secondarily into NXT. If we can pull PTS into a solid uptrend, there will be a lot of eyes on Bitshares.org that feeds back into the system. If PTS merely doubles, it outweighs any amount of AGS donations in the remaining 40 days.
Put another way, if PTS merely doubles we could easily spend 2 million dollars on whatever is needed, and then it would surely double again, at which point we reach escape velocity.
The most important consideration of all is to produce hype on command IF BTC approaches new all time high, or NXT keeps climbing to challenge LTC. As every surfer knows, when the big waves are coming you need to paddle like a crazy person on command at just the right time.
Notice that a lot of these points are in conflict, and we need artful judgement to find the optimal tradeoffs in each case.