Once you've crafted an amenity, you can always install it again using the Arrange option. You don't have to re-craft it! The Arrange option is invoked by the grid icon that is shown at the top right of your screen when you're at your camp site, fourth from the top. Select an amenity spot and use Place Item to select which amenity you want to install.
If you've crafted the highest level, you can't display the lower levels anymore. There's a strange anomaly regarding the snow park. If I look amongst my Amenities, all amenities are shown as the highest level that you've crafted them, but for the snow park, it shows Level 1. I was like, what!? I'm sure I crafted Level 2! If I then place the snow park, it's indeed the Level 2 one. The Level 1 one is shown but it can't be placed anymore. If you haven't crafted the Level 2 one, you can still display the Level 1 one, obviously.
Oh. Amenities are what this game calls the two north areas of your camp. So the tents, stage, skate park, pool, hot air balloon etc. The 'areas' you craft that allow you to raise (up to the max of 20 - for now) all animals with the same personalities levels up. I don't think that made sense too well and you probably already know this but; if you don't level up amenities or craft new ones no matter how many requests you fulfill for an animal with that type of personality, your friendship will never be able to rise with them.
But you're absolutely correct about needing to re-craft items if you want another of the 'basic' color-scheme of an item that has multiple skins. I know I have done that with all of mine because there are a few I love basic style over the 'new' style.
Luckily, it's a LOT easier to come up with the materials to re-craft items than it is amenities! At least it is for sure when you get to needing 60 essences for a single level up. Especially when it doesn't change the way the amenity even looks!
AC:PC +- Level: 138 -+
Active (daily) requests only please!