Its hard to say really.
As I see it, the focus of game developers tend to shift from desktop computers to consoles from time to time, today we seem to have a strong market for console games despite their relatively high costs, eventually we might see the focus shift towards the desktop platforms again and perhaps then the Amiga can take a part of it.
As for titles, i think it is important to have titles not present on other platforms, but since most games get ported for finacial reasons, there is most often no titles to show off with, especially when it comes to Amiga.
To grab a big marketshare, i believe we need good quality games not avaible on other platforms, they also need to be cheaper than both consoles and PC games, an unlikely combination.
Perhaps there is a potential if developers within the Amiga community cooperate more, and more open source solutions become avaible, like 3D engines etc, that are of high quality.
Education is also an important part, online courses and material might boost the number of developers, aswell as titles.