According to my point of view.
This game is not a failure overall. Though it has some issues, devs are working on them (my game has already been patched 3 times via steam).
By lag if u mean performance then its not outstanding but still the game runs quite well on my core i7 2700k and Hd6850 gfx. I was still able to run the game on my laptop core i5 with build in intel hd4200 and it was playable.
For making the game more lively, i dont know about the devs but i believe that there is a lot of potential in the community to release mods (there are already mods in development)
For some games like Locomotion, community developed items were better than the games default items.
Overall I would recommend this game to anyone whether he is a transport tycoon fan or not.