Maybe you should look at the RHA MA750. Its bass is enhanced and have great mids and highs. 

I had 2 Senns CX300, one mark I and one mark II. Although the sound was not an straight disappointment, it wasn't great. Not to mention that both gone within 5 months of normal use.

If you want a truly indestructible IEM, you should look the SE215 in my opinion. Mine's broken because I stepped on it with my protection footwear haha. Also they may have the frequency response that suits your preferences. 

I don't know if that counts as a deal but Focal Spirit One S for 118.69 USD through Amazon. https://www.amazon.com/Focal-Spirit-One-Premium-Headphones/dp/B00KFQMIVS/ref=sr_1_1?ie=UTF8&qid=1490153667&sr=8-1&keywords=focal+one+s

  Maybe you want to try the SHP 9500 from Philips. They are open and a good sounding HP, and altough the philips don't have the inline remote mic, you can connect any 3.5mm cable to the headphone. So if you buy the SHP 9500 with Vmoda with inline mic cable it can be the solution.

This.   Besides that the K7xx series need good amplification. They will need more power than your current setup is capable to give.

The Fidelio X2 seems to tick all the boxes. They are open though.

Vsonic GR06 >= Vsonic VSD3 > Shure SE215 > Vsonic GR02 Bass Edition > Meelectronics S6P = Meelectronics M6 >= Sony MDR EX100P > Sennheiser CX300 > Marshmallows

Hi guys.   I will recommend the HD558 from Sennheiser, it surprise me when I put it on my ears, also it have a laidback caracter and the highs are not pronounced in any way. 108 US Dollars in amazon.

Hi!   The hd439 are very good headphones for its price at this time (45USD-Amazon). However when you say large and elliptic ears the HD5x8 series come to mind. If you can buy the HD558 and don't mind the isolation... just do it.

Hi!   Try Yamaha EPH 100.

Hi.   When you say a decent priced item, we would like to know what is a decent price for you. So, you can tell us your budget? Can you describe the sound signature that you want? bassy or clear and detailed.. etc 

+1, when I listened the 518 it sounds different to the 558 (558 sounds better though) but I think that is not worth buy the 558 when you have the 518 already. The logical improvement are the fidelio x2, it costs 300 dollars but you can buy a used pair for 240.

oh :/ sorry about that. Maybe this feeling is caused by pleather pads, so I suggest again the SZ2000 with HM5 velour earpads.

Some people have reported issues with the i version of the RHA MA750, however, you have a 3 year warranty and it's probably your best bet if you want a good iem with mic and remote. The remote cable for the shures seems to be awful.

Hi.   Some people praise so much Superlux for cheap and great semi-open headphones, look the HD668B it appears to have good soundstage for its price (45 US Dollars)

Hi.   The only model that comes to my mind is the Denon D600, very comfortable and similar sound profile (although I think it will be far superior than inspiration's)

Hi! Your idea of bypass the sound of the jack through the 30 pin conector is easy and is not that expensive (For 37 US Dollars you can buy a FiiO E6 and a L9 LOD Cable). Is exactly what I would do.

Hi, i suggest the RHA MA750i, great sound and have the in-line remote and mic.

From what I remember the Sennheiser HD 380 Pros have huge pads, bigger than HD558/598 pads and HD650/600 pads.   EDIT: The Brainwavz HM5 and K702 (Same earpads in Q701?) have huge earpads too. Some Measurements from other thread ("Size Matters - Earpad Hole Measurements for Over-Ear...

You're Welcome!   From what I remember in the listening of my friend's M100, the soundstage is not a strong point, however reading further about the XL pads, people say that improves comfort and soundstage as well. You should give it a shot IMO, however I suggest you to make some measurements...

+1

Hi.   Ok i don't understand very well, you say that you want some DJ headphones (is my understanding that DJ cans must have great isolation for the stage) but you suggested an open back headphones too (and open backed headphones don't isolate you from external sounds). The XL pads for M100...

+1, RHA 750 and Vsonic VSD3 (and VSD3S) are apparently great headphones too. I have to add the GR02 Bass Edition to the recommendations.

Hi! you can try the Shure SE215, the bass is prominent but not much, sweet mids and highs and outstanding isolation. 99 US (amazon). If you want more bass, you can try the Meelectronics M6 (or M6P for mic and in-line remote) but it don't have the resolution of the SE 215 and it have a u shaped...