Here's an anecdotal experience for you.

After playing quite a few games of E:LH in the last several weeks, I went back to and played another game of E:FE.  That game (E:FE) felt dry and uninteresting to me by comparison.  Most of the 'backbone/gameplay' of the E:FE game is E:LH, but there is quite a bit of new stuff in E:LH that quite simply isn't in E:FE...

More quests, more interesting locations on the map, combat has a LOT more options.  Better game in every regard.

If I could have all these options we have now merged with the original E:WOM structure, with one or two E:FE concepts that have been replaced, I'd be absolutely loving things right now, but I digress....

If you liked E:FE, you will very much like E:LH IMHO.

E:LH (Though very buggy currently) is fantastic.  The custom leveling of heroes is something I always dreamed of for E:FE. 

The swarming rules (at first glance I thought it was too much, but that was until I really started watching the numbers)

The addition of weapon and shield specific abilities add some interesting battlefield dynamics such as flanking and pushing opponents so you have to really look at the weapons you are using rather than just for the highest numbers,

Many of the spells that had two elemental requirements or special spells that were given out randomly have been added to the mage tree, which makes them more accessible but more expensive to obtain.

It's an amazing game even given the buggy nature of Beta.  I cannot wait until it goes live.