lol @Egon. What an epic dream!
I’ve developed a bit of a habit in collecting pretty much just green throws! 
I don’t really have any specific habits or rituals or anything out of the ordinary that I can think of.
I do like to count things…but that’s not just with yos, that’s with everything.
When I get new strings I like to count them…just counted my green kitty fats today randomly (79 left lol).
I have too much spare time on my hands! >.<’
I keep a list of every yoyo, along with what string, bearing and response are equipped. Organized by yoyo brand and name alphabetically. I have over 150 throws so this list is getting long. They are likewise organized in cases.
I tend to prefer nylon or nylon/poly on bimetals. Poly on monometals. But this is more of a rule made to be broken, if I really like a throw its probably getting a nylon string. I have not been able to find a bulk string I really like. The way the string feels and responds has to match the yoyo or it bugs me.
I’ll swap bearings, strings and axles until I get just the feel I want from the yoyo. I keep every different kind of bearing and a variety of response pads and silicone on hand so I can tweak until I’m happy. This is kinda crazy since I’m not a great player. I’m just particular about the way they feel.
I try to put contrasting string on every throw, if I don’t have a color that suits me I go searching the various string vendors looking one that does in the right blend and thickness, I may order several different strings if I’m not sure. If I can’t find a string I like, I probably won’t throw it until I find a string. Even if its a throw I’m super excited to get. I’ll throw it just enough to make sure it plays right. It’s not much of a problem now, I have a ton of nice strings. I’ve thought about taking up string making, but I’m 100% certain that is a rabbit hole I should avoid.
I always check string tension and make sure its nicely wound before I put a yoyo down. I always do a safety throw first. I got compulsive about this after I smacked myself a couple times.
I tend to play a type of yoyo in groups, it might be organics for a while, then high performance bimetal V’s, then old school stuff, then relaxed monometals, then big throws, etc.
I might have a little ocd.
Wow I feel ya
I do believe I also have a bit of OCD
Hell sometimes I put on toothpaste 3-4 times on a single brush to get exactly that perfect streak of paste on the middle
Another, I will probably never sell a yoyo. I hate dealing with selling things. The whole business of listing it, making sure I get the condition accurate, deciding on price, and then packing it and shipping it while hoping I got the address right, going to the stupid post office. I would have to really really be hurting for cash to bother.
On the other hand I’ve given away a lot of yoyo’s to friends and family who show interest. I picked up a bunch of b-grades during May and I’ve given most of them away, except the ones I wound up liking a lot. I was trying to decide on a good throw to give away earlier this week, and it was tough deciding what I was willing to part with. Time to watch the BST, and YYE’s bargain section for more give away material!
Im not quite that particular, but I do similar things. A lot of my favorites will get the nylon treatment, but poly on other favorites because I like both types of strings for different reasons. Snaggy yoyos get concaves and grooved bearings, organics typically get flat bearings, and everything it between gets a CT or some other similar string centering bearing (occasionally you get a yoyo that comes stock with a premium bearing like an NSK, and I will stick with that). Thick strings for yoyos that don’t quite have the tightest binds, etc.
I used to deshield, clean, and lube all new yoyos with their stock bearing, but ive seen some compelling arguments about breaking bearings in, so I will usually play with them for a few hours brand new before making any changes.
Im also with you on selling yoyos. It isnt worth my time, and I just like to cycle through my throws just to appreciate the differences in feel.
I’m a little obsessive about tension and clean binds. I’m a lefty, so when I throw the string loosens, and I tend to over-compensate and make it too tight so I don’t have to adjust tension as often. If I feel like I get a sloppy bind on a breakaway, I always throw a front-style throw to fix it.
I also ALWAYS have all my yoyos in a Throw Bag or paracord holster when I’m not playing with them, so I can grab it and go when I leave the house no matter which yoyo I decide to take. The only exception is my Lowkey Woodland, because it always goes in its fancy wood box when it’s not in use. I’m sure this won’t continue as my collection grows, but for now I only have a few yoyos so I have enough holsters and Throw Bags to keep them in.
The only string color I can use it neon yellow.
I don’t know what it is, but I feel like strings that aren’t yellow don’t play as well, even if it’s the same exact type of string in a different color 
I know this isn’t founded in any sort of reality, but I can’t help it!
I agree that highlighter yellow really pops against everything - especially when it’s clean…neon orange follows yellow in visibility for me personally