Yeh they are garguantuan and awkward machines the 5500... my first ever Powermac was a standard white 225 and it was at the time, a slick, fast and capable rig, and I have always had a soft spot for them. But yes, the plastics are among the worst I have ever seen on any Mac to date. It literally gives way in your hands if you pick them up the wrong way. If I ever find a mac TV for sale in Australia I will probably be all over it... They are one of my grail machines and always have been. 
At this stage I am in no big hurry to repair the DE as even when I do, I have no place to permanantly install it (as it is way too heavy to be moving in and out of rotation like i do with my desktops.
But yes, I'm at the stage now of sorting through what I have, dragging out the rarities and particularly volatile machines first and working out what works, and what needs to be done to make others work, and preserving the best examples of the other stuff, and working out what is to be reduced to parts, what can be kept for future trade. Realistically the Oldworld PPC and 68k portion of my collection stems largely from the period of time around 1999-2005... at that stage I was basically in the mindset of collecting AAAALL OF THE THINGS. If I saw a grey Mac somewhere, I bought it no questions asked... Same with accessories. As a result I ended up with huge numbers of duplicate machines (eg. I have 4 7600's, 2 7500's, 3 7220's and at least half a dozen 63xx machines) and a cupboard full of peripherals. The NewWorld stuff is mostly from the period from 2006-present and whilst I went out of my way to procure some of it, a lot of it just found me by chance... usually because friends would end up with access to a haul or replace their individual machines and automatically asssume I wanted them. As a result I have about a dozen complete iMac's and as many that have been reduced to parts, as well as an eMac, my Power Tower collection (which techcnically dont count as they have largely been my succession of daily driven machines) and then my pair of Lombards and Pismo. Obviously there are a few old world things I have received more recently such as my 2nd IIvx and my 9600, which were machines I actively went out of my way to get, but realistically I havent collected much OW/68k stuff for around 10 years.
At this stage I am in no big hurry to repair the DE as even when I do, I have no place to permanantly install it (as it is way too heavy to be moving in and out of rotation like i do with my desktops.But yes, I'm at the stage now of sorting through what I have, dragging out the rarities and particularly volatile machines first and working out what works, and what needs to be done to make others work, and preserving the best examples of the other stuff, and working out what is to be reduced to parts, what can be kept for future trade. Realistically the Oldworld PPC and 68k portion of my collection stems largely from the period of time around 1999-2005... at that stage I was basically in the mindset of collecting AAAALL OF THE THINGS. If I saw a grey Mac somewhere, I bought it no questions asked... Same with accessories. As a result I ended up with huge numbers of duplicate machines (eg. I have 4 7600's, 2 7500's, 3 7220's and at least half a dozen 63xx machines) and a cupboard full of peripherals. The NewWorld stuff is mostly from the period from 2006-present and whilst I went out of my way to procure some of it, a lot of it just found me by chance... usually because friends would end up with access to a haul or replace their individual machines and automatically asssume I wanted them. As a result I have about a dozen complete iMac's and as many that have been reduced to parts, as well as an eMac, my Power Tower collection (which techcnically dont count as they have largely been my succession of daily driven machines) and then my pair of Lombards and Pismo. Obviously there are a few old world things I have received more recently such as my 2nd IIvx and my 9600, which were machines I actively went out of my way to get, but realistically I havent collected much OW/68k stuff for around 10 years.