If it remains as it is, I don't expect it to last very long.
The only incentive to come back once you have completed the first stage is loot (and that won't be an incentive for people who got the mount etc while levelling).
Since you need to group with people of a similar level to get XP, Eureka doesn't appear to be very friendly to people starting late or progressing slowly due to time restraints. In other words it's not casual content (using the definition of casual = limited time to play).
It's not solo friendly. The XP you can get alone is very low and if you die you are dependant on a player who can raise being in your vicinity or being kind enough to go out of their way to help.
On the subject of the 'Death Penalty', I see a lot of people defending it and saying it's a fun mechanic but a lot of them are also saying things along the lines of,
"Anyway, it's very easy to get a raise, so if you lose XP that's basically a choice you made."
That says to me that they are enjoying the illusion of danger while knowing there is actually very little risk of them losing XP or delevelling due to the high numbers in the instances. When fewer players are in the area and the risk becomes real, I think that penalty may prove more of a disincentive.
Since there is only one thing to do in the area, I expect boredom to become more of a factor as time goes on.
The lack of story, the inability to play with friends and the very long grind on this step are probably going to sap a lot of people's motivation.
