There are a handful of amazing features PoE offers that downright put Diablo 3 to shame, but the aforementioned gameplay elements are more integral to the ARPG experience and therefore make D3 the better game in my eyes. This goes without saying that Grinding Gear Games have done an absolutely phenomenal job at developing PoE over the past 4-5 years.
So what would I like to see in Diablo that Path of Exile does better?
The biggest feature I'd love to see in Diablo 3 that thrives in PoE is the incredible structured PvP. Here we have events (races), ladders, and a hugely diverse and competitive community, all aspects that would help repair the quickly disintegrating social front found in our beloved Diablo.
I would also like to say the itemisation and skill tree found in PoE would be a welcome addition, but integrating a similarly complex system into D3 at this point is unrealistic and would require a complete reset of the game's player base progression and economy. That said, the upcoming itemisation changes in 1.09 look extremely promising. Here's hoping that we are finally excited about drops again (and no more of those silly 'broken' stat rolls; WD skills and Str on a crossbow anyone?). This is what I hope the team works on the most, giving us some much needed diversity in the items and skills we find viable. I'm most interested to see how the low level legendaries perform with endgame stat rolls.
On a somewhat unrelated note, wouldn't it be great to see what the expac is going to offer? My personal expac wish list is so big it would require a whole new thread.
TL;DR- You're lazy, and probably wouldn't contribute much to the thread anyway. ;)