I do hope Centra does go on major exchange as I do not like to trade on ETHERDELTA. My Wife complained of many problems on that exchange so I will wait for one of the other more reliable exchanges to trade. We bought over 8 Ether worth in Pre ICO so I would only trade a little portion of it anyway.
Indeed your right!, if Centra goes on to major exchanges, it will spread the word about the project and will ensure an even distribution for every stakeholders, thereby keeping the price as healthy as possible.
The way I have heard of projects with alt coins were from being listed on th cryptopia exchange first.
Since they have a "featured coins" scroll bar with the featured ones and not the most traded ones like the bigger exchanges have on their scroll bar like bittrex and poloniex has.
This is how I knew about the four or five coins that I have collected over the past year just from that featured series on the smaller exchange.