To be very honest, it was the summons that really sucked me into the game. I don't mind the conversations (the intro to GS was pretty long, but understandable considering they wanted to plant plot/storyline and not pick up and go like some common NES Mario game), but for me I was estatic everytime I found a new Djinn because I knew that it meant I'd get to see a new summon (and when tLA came out, I was even more estatic to see combo-summons). It honestly wasn't until half way through the first game (the first time I played) that I realised that each Djinn had powers of their own (I just set each Djinn before each battle).
It might seem like overkill, but I'd love to see a summon that takes ALL Djinn to summon it (it's a bit of wishful thinking considering GS/tLA had 42 Djinns all together). When it comes to new summons, I suppose all we need are every possible combination of every elemental Djinn.
*Goes and watches the trailer again to see his favorite Eclipse summon*
-BGS