OP ... welcome to Cruise Critic.
$12K is a serious boatload of money to spend on a vacation. And you need to be comfortable with your decision, whether it is to keep your Royal booking or switch to a different Princess ship, or even back to Celebrity.
There's a lot of "don't worry, be happy" on this thread, much of it from Princess loyalists. Comments here are to you as anonymous as those negative ones you've seen that are causing you angst.
I learned a lot last year about some of the issues surrounding the Royal in Alaska. Most telling were the comments from the pilots. Frankly, given the issues, I'm surprised that Princess redeployed that same ship to Alaska for this 2020 season.
Yes, it's a lovely ship ... but you might feel more comfortable with Princess on a different ship.
I cannot speak to the Alaska experience on Princess (we went some time ago with a small-ship company, no vessel with more than 100 pax) but anything I've read always has been very favorable.
I hope that you will weigh all the knfo you find here on CC and other internet places and reach a decision that will give you reason to look forward to a glorious vacation ... rather than experiencing so much angst.
Safe and happy travels!