Rolls around to the computer and sees name being mentioned while half drooling
Ok, so pets are being discussed.
Alright, first things first, immortal Familiars were indeed fixed, way back like a good amount of patches ago.
But Pet builds are still strong and there is no content they cannot tackle as of this post.
For the purpose of this thread, if you are looking for an endgame build, Pets do require full sets. Hell, my Will O Wisp Cabalist uses 2 full sets…
But if you are looking for a budget build that can help you farm, then head over to here: The Carnival - A Guide to Pets
Do note that my tests were all done on Single Mastery Occultist & Necromancer as I am too lazy to select a secondary mastery for budget setups 
I haven’t tried Dungeons after the difficulty update, but before that my Occu was steamrolling them on Ultimate. My only experience after the difficulty patch was with BoC, where I died to Sharzul and said nope.
But I am a terrible pilot and I was using a Single Mastery Budget Build. Keep that in mind.
As for SR, are we talking, normal, elite or ultimate SR?
If Normal, then you can easily farm 65-66 without trouble (I don’t like the maps for <65) & get like 7+ legendaries per run. Monsters also do not regain health even if you die.
Also, as a bonus, you can wear Lokarr’s set from 1-100 without having to worry about the low armor getting you killed. Hell, you can even wear it while Farming SR. I know I did 
Note: In case anyone is wondering why I used Single mastery builds, the reason is simple. That way, you can pair it off with any mastery you feel like going with instead of locking yourself into the traditional Conjurer/Cabalist/Ritualist role. It also lets you go with a completely different, non pet build later on should you feel like it, provided what you want uses Necro or Occu as one of its masteries.
If you want an endgame build that doesn’t use full sets, then I can give you a Cabalist here: https://www.grimtools.com/calc/0V03WMa2
If you want a Conjurer, or something else in a similar fashion, let me know and I can make one for you.
Also do note that I prefer defense over offense, so all my builds tend to be built to take on Heavy Spanking* & while they can dish out a fair bit of their own, the focus is being extremely hard to kill than setting records for clear speeds. (I focus on Superbosses mostly, so the defense oriented approach is kind of needed)
EDIT:
Pics of SR runs with Solo Necro wearing Full Lokarr’s Set:
50-51 : https://imgur.com/PnviYmV
55-56 : https://imgur.com/MXxeYKh
60-61 : https://imgur.com/EJLelVG
65-66 (time ran out) : https://imgur.com/1cQAd0J
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Do note that I was curious about the number of legendaries and hence the loot filter was set to that. Hence the lack of items other than purple ones in the first 3 pics.