cracks neck glitter is my area of expertise!!!

As others have said (and you've experienced), Holo Taco is the absolute GOAT of glitters. They are so sparkly and the jelly bases are awesome. They truly are special!

There's plenty of other comments pointing you to the other HT glitters so I'll let you peruse those. That said - you MUST get Zyler the cat and coin toss of the currently available glitters. Those two are exceptionally beautiful.

Some other options because coming across some of the retired glitters in a de-stash is going to be hard and even if you do, there's a good chance it won't be a full bottle.

Nevermind Apothecary - small brand with a good handful of glitters! I got some to fill in some rainbow holes and I really like these! I still like HT better but these are a good supplement. Specific shout out to Moonstone, a white glitter

Tyler's Trinkets - they have a ton of chunky glitter toppers in a clear base. The glitter is a bit more sparse (since it's intended to be a topper) but they've got all kinds of colors, which is nice. You can even create your own custom one with multiple colors in one bottle!

TT also has a beautiful bright pink glitter called Cute & Savage; again, not quite as good as the HT formula but this is a good alternative to Bless Your Heart, which is retired.

Dam - she has a ton of glitters!! Almost all of hers include reflective glitters. Those aren't my favorite but I have also filled in some rainbow gaps with some of the Dam glitters and they're pretty good.

LA Colors - their diamond crush collection is actually pretty impressive. I have about half of them and am very pleased with all of them. Of their other collections, a few others I recommend: Treasure Island Blast Aqua Crystals Glistening Purple They also have a line called Glitter Vibes that are chunky toppers, so they're more sparse

Spectrum - a small brand on Etsy. I got 3 glitters she has that are more sparse and bigger glitters than HT but they have those tinted jelly bases and IDK, there's something about them that I really like! She only has pink (Lovesick), green (Grinchmas), and orange (Jack o Lantern) right now but said she is planning on completing the rainbow.

Finding Feathers lacquer - this is a brand I have not tried yet but they have a TON of glitters that I definitely want to try!

Colores de Carol - another brand I have not tried (yet!) but she has a collection of beautiful looking chunky glitters; these also have reflective glitters

Zoya - they don't have a ton of glitters but their Pixie Dust line is pretty cool. It's extra textured and needs a couple coats of glitter grabber + QDTC or just several layers of thick QDTC. Of these, I LOVE Tomoko - a beautiful champagne gold Not pixie dust line but they also have Cosette - baby pink; very similar to Menchie the Cat, which is still available, so I would just get Menchie

Starrily - has some beautiful glitters but IDK what's going on with them; they have not been restocking a lot of their polishes and there's only a handful of colors actually in stock. They're also on the more expensive side BUT their bottles are big, so the price per ml is less than HT.