Backroads, I'm in the replace as little as possible camp. For the drivetrain I suggest the 14-32T 7S cassette along with a 22-32-42(44)T crankset and a new chain. I'm not sure if a RD replacement would be required to wrap enough chain to prevent chain to chain contact on the small/small combinations.

Add the trekking bars and possibly new cable and housing and evaluate. The toolkit didn't seem too bad, but I didn't see any cable cutters.

Brad