I'm just using the coaster brake on mine at the moment but will be upgrading to a heavy duty 12g spoke front wheel with a S/A drum brake over the winter.
Once you put a motor on it the rear fender will last about a week before it starts to fall apart. I put some fenders off an old Schwinn I found on mine and the front mounting tab was just starting to crack when I made the swap. So if you want to keep the fenders get some heavier replacements, they can be found online for around $30-$40 a pair. I really like the look because they wrap around the tire more.
Take the rear axle apart and make sure everything's greased well and make sure the bearings aren't too tight. Mine crapped a bearing at 25 miles and then the hub cracked at 250. $43 was a very good investment for a heavy duty rear wheel from my LBS.
Ditch the plastic pedals. Mine bent right away, replaced them with Bell cruiser pedals and they've held up very nicely.
Other then those few things my Huffy Cranbrook has held up quite well.
I also plan on going with a springer front end and I think I'm going to have to make up something to go between the fork arms to attach the fender. I know it can be done because the Felt Heritage
uses a springer and it has a front fender.