Black Hills touring help...

Hi,
I’m soliciting route advice from any of you folks who have toured or live in and are familiar with the Black Hills area. I’m planning a trip out there in June and will probably start in Deadwood, ride some type of loop to include Spearfish canyon, then head down the Mickelson trail and loop back on the eastern side by road.

We’ll be camping and be on loaded road touring bikes with 35 or 38C tires to accommodate the Mickelson. Primary help is needed with the following:

1. Return route suggestion to Michelson trail head in Deadwood from Spearfish
2. The best route north of Custer State park back to Deadwood, particularly Needles Hwy vs. Iron Mtn Rd and Hwy 385 vs. Nemo Rd.

We plan on averaging about 45-60 miles a day accounting for the gravel surface on the trail and are particularly interested in a safe route with low traffic or good shoulders. With loaded bikes we’d like to minimize the steep climbs but don’t want to rule routes out if the scenery is worth it.

Also any advice on good camping sites, interesting things to see, and brew pubs would be appreciated.
Thanks!