Open to buy a new pair of headphones.

I think comfort and whether or not you need to be concerned about disturbing a partner who may be trying to sleep will be your primary criterion.  Also a lot depends on whether you will be lying on your back or side, or sitting up a bit.   These are very personal, So I think try before you buy is the best advice.  So see if you can borrow some.  Cable Co. I think has lenders.  If you find IEMs comfortable, they might be the most adaptable but some people cannot tolerate them.  

those headphones vary a lot - have some comparisons based on what I own

[1] Mediocre sound - Bose QC-25; meh sound. muffles base, voice is okay for alto type voices (pop/country/folk), mediocre for complex music (classical orchestral); its really the noise reduction for long airplane rides which I have to do...
[2] Sennheiser HD 600 - a very nice balanced headphone. I’ve used it for all types of listening and compared to my prime stereo system, its a tad "airy" with a good but not profound bass. Tonality is neutral but detailed. Not a "rich" sound, but something very listenable to almost anything for long periods of time. Also, its not very tight or heavy - so mechanically comfortable. Open back so you can hear your surroundings somewhat.
[3] Audeze LCD-X - a great sound. Compared to the Sennheiser, its a more profound sound. Richer texture, a more encompassing sound stage - perhaps it tends to bring up color where the HD 600 tends to dry it out a bit more. These are not huge things, but it is different. This is a heavy set of phones - so harder to sit and listen endlessly with them.

If I had to buy for all purpose great sound with comfort and long-use, I like my HD 600. For the best sound, its the LCD-X. On an airplane its the Bose....

Quick edit:  My headphone amp / DAC is a NuPrime DAC-10H - which is a very fine DAC with a very good SS stage. I've also used a NuPrime uDSD which is also an very fine sound, with a tad less drive - but they both work will with the phones above.  Advice - you will need to spend good (but not crazy) money on the DAC / headphone amp.  You can tune that spend toward tubes and more $$$ to enrich the sound, reduce or eliminate the "SS" sound and so on.  Given I have a tube pre and tube amp on my prime stereo system, I went with SS for the headphones as its dependable, easy, and not running hot in my office...

It will be in my bedroom system that has an oppo cd/sacd player and a Magnum Dynalab 208 receiver.  Thanks for asking.  Jim

What amp will drive  them?

I second AKG. I have a pair of 701s and enjoy them very much, and they do sound a lot like Maggies. You can find a new pair for around $250 Many are now made in China instead of Austria. The ones made in Austria are so printed on the earpiece, and country of origin is also printed on the box. Not sure if they're any better than the Chinese model. Many available on AG, ebay and USAM. 

The problem with many headphones is that you can't lay down and keep them on your ears.  You will either need smaller on ear phones or earbuds.
The big over the ear phones like AKG will sound a lot like Maggies but don't work with a pillow.