Covington will be starting at SF breh, he's arguably our best offensive player outside of Jahlil. Jerami and Jakarr are still both raw offensivey. Wood won't make it over Richaun Holmes
I agree about holmes over wood, but he's already dealing with some injury problems, and their only other backup big is aldemir since landry is out.
Yes covington is an excellent 3 point shooter, but he'll need atleast the same amount of touches to be as effective as he was last season, if not more, and I think the majority of those will be going to Okafor and Nerlens. In the 2nd unit, he can be a more versatile scorer (not just a catch and shoot player) without having to sacrifice his game to accommodate the bigs, He may even get more minutes as a 4 as oppsed to a 3, if Brown decides to exclusively use a 3 man rotation at the pf/c spots (ie. Lakers '09 and '10). If 3pt shooting at both wing spots is necessary Brown can play both hollis and stauskas together.
As far as on D, I wouldn't trust stauskas or hollis, to guard the best opposing wing night in and night out. Jakarr and Grant are much better equipped to take on, melo, lebron, derozan, johhnson, george, butler, harris, giannis etc. for the majority of season. That's if the sixers are realistically competing for that 8th spot.