Seconded. This would be especially burdensome for anyone that plays multiple characters. It's one thing to have grinds that people can get done faster than you because they prioritize them, or have less IRL time restrictions etc; it's another thing entirely to say "not only can you not reach as high a tier as quickly, you can't keep it once you have it.
Losing progress feels horrible. Imagine if enhancement runes decayed over time, or even if you weren't using that LI (say my DPS set for my LM). Or if you had to "re-earn" virtues, or faction reputation. I can't imagine that ever getting proposed or accepted, and I don't see the difference between those and guilds. Don't take things away from people unless they choose to lose it. (e.g Ale Association and Inn League. That's perfect because it's a choice).
Choices are fun, progressing your journey is fun, even if you have to do it an inch at a time when you finally have a free hour to log in. Treading water is not.
"We know that the length of time needed in order to increase standing with guilds is prohibitive." Adding a grind to stay at full standing undermines any feeling of victory you would get for finishing the grind, even if it is shorter.
And if reducing grind time is the goal, I don't see how adding a grind where none exists would do that.
If you want people to actively engage in crafting, rather than just making it a one-time thing, some of the other ideas are better. Participating in limited-time crafting events or cranking out some quests to get the best stuff, that's good. It's the same for people running Thrang to get the best pocket items. Need mithril for the best jewelry? Join the Moria expedition as they uncover a new vein, that will only last so long.
On the whole, I like a lot of the points, just want to shoot down what seems like at minimum a frustrating change for no benefit.
Custom profession combos? Great! Never got much use farming or weaponsmithing on my historian, but maybe now he'll cook some bread and write a book by the fire.
Additional slot? Amazing. My armorer will love being able to tan hides on his own.
Useful crafting gear beyond just "done with quests, haven't done instances yet?" Awesome. What I want from it. To not *just* be a stepping stone I use for a couple weeks.
Decorations / housing utility? Wonderful. I have a friend who decorates every house he buys (6+?) in exquisite detail, and always wants more options. I'd love to provide them.
Crafting Events? Perfect. As I noted above, I think they are a much better solution to "repeated engagement" with a crafting profession than a forced continuous grind. Working for something shiny is good gameplay. Working to survive is well, real life.
Thanks for opening this up to discussion. I've always love LotRO's crafting, and I'm excited to see it get some new life and attention.