Is the Chepe ever full? I only travelled a short section between Posada Barrancas and Creel in July 2015, but there were plenty of empty seats on the train. In the 4-5 days we've spent in the Copper Canyon, I saw a grand total of one foreign tourist (and that was in Creel), so I'm not sure how busy it gets. There were quite a few Mexican tourists, but there was still plenty of space on the train and in hotels.

I'll be going there again at the end of July / beginning of August and do more of the train trip this time, so I may be able to report back before your trip depending on when exactly you'll be there.

Thank you!

We have a total of 14 days on our trip. We are bypassing Kanab. We fly in and out of Vegas and are spending 2 nights there. I hear Valley of Fire is a must from Vegas and we already plan to kayak through Black Canyon. Everywhere else, we have 2-3 nights planned in each area. Zion and Moab we have 3 nights each. We won't have time to do any trips from Page, as we will be driving through and stopping to do Antelope and Horseshoe Bend on our way to St. George from Cortez, where we sleep before heading to the airport the following afternoon. (long drive, we know)

When it comes to driving distance, we don't mind.

We are in pretty decent shape and definitely capable of some pretty strenuous hikes, but we don't rock climb or do anything extreme.

As far as the Grand Canyon, I know that is a separate trip we plan to make, in an attempt to not over commit ourselves and stretching our time too thin. There is so much to see and do in this whole area, it is overwhelming for sure! We are doing a mixture of tent and cabin camping and staying in hotels/airbnb's. We intend to tent camp in Bryce Canyon for one night, but I know we cannot reserve this until we are there.

I've read about Jacob Hamlin Arch in Grand Staircase, but know that it is pretty difficult and I am not entirely sure where the trail head begins, if it will be feasible for us. Grand Staircase I think is what I know least about. I've read about the slot canyons which sound great, and the upper and lower creek falls, but this is an area I am not sure what to cover exactly.

Michigan isn't on the list other than to visit family. Michigan is my old stomping ground, having spent numerous summers in Beulah with grand-parents. Same reason I'm not going to Ann Arbor; that's my other grandparents.

I double down on the suggestion for people to go to Sleeping Bear, except I've been there many, many times. I even dragged my wife up the main dunes and all the way to Lake Michigan by foot. We were younger then. There's no way I'd make it any more. But for anyone even close to that area (basically the north west portion of Michigan's lower peninsula), I'd strong recommend it, too.

The GCNP North Rim is closed until 15 May, so that's not an option, and it only would have saved you a couple of hours in any case. And we preferred the South Rim. It doesn't matter which order you do the two parks in, it seems to me.

Apart from walking along the rim (shuttles to the west of the Grand Canyon Village, driving to the east), there are a number of walks below the canyon rim, and it's enjoyable, although fairly steep in parts. You can walk down as far as you like, allowing good time for the return trip to the rim.

If you search on "Virgin River kayaks" you will see a number of options in Springdale (as an alternative to Lee's Ferry at Marble Canyon) - although your time is really limited.

On the road between Springdale and Las Vegas, I recommend you visit Valley of Fire SP - it has a couple of good walks, and is a really nice park.

Is there a reason you just don't fly into Las Vegas and skip LA.

I also agree Meteor Crater is an overrated dirt brown hole tourist pit, $18 bucks pp to see that. Remember it's not to far from Flagstaff but over 2 hours one way from the Grand Canyon, probably the most mediocre place on your list.

Use Sunday morning to drive to Las Vegas and Sunday morning to return to LA, much easier drive on weekend, otherwise your in a traffic nightmare.
Try not and over do it, enjoy your trip, do some short hikes, enjoy the scenery, have a cocktail-maybe a couple!
Another option.....

1- Night - Sunday - Las Vegas
2 N - Grand Canyon via Hoover Dam and maybe Rte.66, Kingman-Peach Springs-Seligman-Grand Canyon, try and stay in the park. You want to be by the rim, enjoy the sunset!
1 N - Bryce - Stay in the park
2 N - Zion - Stay in Springdale
1 N - 29 Palms for Joshua Tree, your much closer to LA for your flight out, drive JT Sunday morning and leave for LA around noon, no later, to avoid late afternoon traffic.
LA - Fly out

last day in Yosemite (challenging hike - Mount Hoffman? Yosemite falls? Mount Dana?)

Try to get a permit for Half Dome.
The hike takes you right by Nevada and Vernal Falls (which you should see anyway). Don't try this without a permit. There will be a ranger waiting about a quarter mile from the chains checking permits. You don't want to hike for 6-7 hours to find that you can't go any farther (I've personally seen people turned away).

Four Mile Trail is termed the "steepest trail" in the park, and leads to Glacier Point, a great place for sunset (which you'll experience with plenty of other people who drive there instead).

12 - staying near Bryce Canyon

You don't need a full day for Bryce. It's small, and the Navajo Loop Trail is the best trail there.
Instead, you could spend this night farther north. I also recommend Capitol Reef, but you could also spend it in some of the higher elevations of Grand Staircase-Escalante around Boulder Mountain. This would also allow you to try some great hikes in the area, like Calf Creek Falls.

18 - 2 hours drive to Grand Canyon or going for a raft experience

A "raft experience" in the Grand Canyon is more than a day's journey. A day-long raft experience will not be in the Grand Canyon.

You mentioned Tom´s place few times but I didnt find lot of information about what we could do there.

The place itself is more of just a place to stopover/spend the night.