I rank this as one of the top day hikes on the North Shore. Despite the cloud cover later in the day, we had fantastic views to Sky Pilot, Garibaldi and Mamquam, the Tantalus Range, Robie Reid, Judge Howay, Five Fingers area above Pitt Lake. To the south we could make out Mt Rainier, and even the Olympics, floating above the Gulf Islands. We had annual passes for Grouse so getting up and down was "free" and though Grouse was busy, we left the crowds behind as soon as we headed for Goat. We saw maybe a dozen or so other hikers the rest of the day.
The trail was kinda muddy in places, but that's to be expected given the rain we had this week. Some parts have slippery roots which require caution. Note that the powers that be on Grouse have relabelled the trails: follow the Alpine Trail to get to Goat Mtn and Ridge and to Crown Pass. (The so-called Ridge Trail goes up and over Dam and Little Goat, while the Thunderbird Trail heads out onto Thunderbird Ridge.)
I was struck by how far behind many of the plants were: most of the berry bushes seem to have not even flowered yet, let alone fruit. We saw fresh arnica, white rhododendron, partridge foot, hellebore, copperbush and pink and white heather. I have no idea what the bears are eating up there 'cos there aren't any berries yet. Hopefully they'll come on soon. Of course, with spring-like flower conditions, it means that we have spring-like bug conditions... We were swarmed by blackflies for most of the day though I don't think we got many bites. A few mosquitoes joined in just for old time's sake.
We continued along to the end of Goat Ridge, adding another couple of km and about 150+ m in elevation. It's pleasant terrain that invites exploration. There are few little tarns dotting the ridge, but they're quite shallow. We've wanted to do this for ages and it was well worth it, if nothing else than for the solitude. We saw one other person on Goat Ridge, a guy in his 60s redoing some of the flagging. There is one section on the ridge where a plastic chain is in place for additional support when ascending/descending a 3-m step: the anchor loop for this chain is starting to show signs of serious wear and tear, and I have no idea how much longer it will last. Test it thoroughly before relying on it. There's enough ambient vegetation to get up and down without it if necessary. Note the return from the end of Goat Ridge is mostly uphill - keep a little energy in reserve :-)
On our return we took a flagged trail up the back-side of Grouse summit (getting soaked in the process as the bushes were still wet) and emerged very close to the Peak Chair where we joined the line-up for the scenic descent back to the main area. Highly recommended!