I know CiV counts Wonders very heavily when figuring score - you build a wonder and your score goes WAY up. 

How does it work in EL?   I played on regular difficulty for about 150 hours and always had no trouble being the score leader. 

After the Shifters patch I'm always in the bottom rung for score.  

Is the score that meaningful?   In CiV if you get too far behind you're going to get left in the dust.  

I'm trying to figure out how I can stay more competitive and having a tough time of it.   

Any comments or suggestions welcome. 

As far as I know, the AI uses a similar calculation to that score to determine whether you're more powerful than them or weaker. Based on this (and other factors) they decide whether to attack you or not.

I think the score is mainly based on your armies (I think HP is the determining factor here) ...

See this page:

http://endlesslegend.gamepedia.com/Victory#Score