aha! Thank you. This gives me a start. Is it just personal preference on prototype boards vs. hot glue vs. soldering?

Learn to solder, it's fun and easy. I really like this vintage PACE electronics series, and learned a lot from it: https://www.youtube.com/watch?v=vIT4ra6Mo0s&list=PL926EC0F1F93C1837 . The main problem with soldering is buying a solder iron that's not the $15 crappy ones. This Hakko is what most people seem to have, it's a great station for the price. https://www.amazon.com/Hakko-FX888D-23BY-Digital-Soldering-Station/dp/B00ANZRT4M

If you aren't going to solder, check into posi-locks. I use them for quick prototypes, but they'll hang in there for lots of uses. https://www.ebay.com/itm/293853836834 . Or, use solder seals. These things can save you a ton of time in some situations, when you're just doing a few connectors per unit, or your big connectors to the power supply. These things are bulletproof. https://www.amazon.com/VOLT-Connectors-Soldering-Connector-Terminals/dp/B07DRDWFDB There are a surprisingly large number of no-solder connections - there's a great one I found just last year that's like a 5-way splitter, great for your power or ground planes, has meant I don't need to put together a board in a couple of small builds.

But realistically you'll need to do some soldering to even just attach some wires to the board, so you can use these no-solder technologies after that. Buying a bundle of male-female 4-pin JSTs solves a lot of that, you can do the one solder to the board, then everything else is solderless.

Besides breadboard, you can also get perfboard. I tend to build first on a real breadboard with jumpers, then put together a few units on a perfboard, then if I'm going to make more than 4 or 5 of something, pull down Eagle and send something off to OshPark.

One thing: I find invaluable having "buck converters". Here's an aliexpress link but you can find them lots of places. https://www.aliexpress.com/item/32708810351.html This allows you to standardize on a certain voltage power supply, or pick the power supply your LEDs are running at, then step down to 5v or 3.3v. For example if you use 5v LEDs but want to use a mix of 3.3v and 5v parts, or I buy nothing but 12v power supplies now and just step everything down to 3.3v or 5v or both, depending.

You can find little "project boxes" to put it all together. There's something called "conformal coating" you can apply to a board to make it waterproof, if you want to go that way like for a wearable, and minimize whether you even have a box. If you have a 3d printer, learn to make little boxes - you can print standoff and whatever you need for holes, if you get even half decent at design. The free copy of Fusion360 and a $200 printer will get you a long way but you'll go down the rabbit hole of 3d printing :-)

You also might reconsider using arduino-qua-arduino. With ESP32's running between $4 (chinese sourced) and $11 (american sourced espressif manufactured), and supporting the Arduino software environment, I find it hard to use those stupid large arduino boards (I guess they have micros but they're still big!). There are some great ARM CORTEX dev boards too - besides adafruit and sparkfun (which tend to be a little pricy) there are lots of choices (like small ones with good battery support Tinypico) and slightly larger more bare bones ones (ESP32-PICO-D4).

Good luck, it's a big jump.