Processing is not an issue at all, it's one of his strengths, especially with the puck. His skating is quite good imo, but he may lack elite top end speed. His poise with the puck and decision making when under pressure (both defending the forecheck and on the offensive blueline) is very impressive. His turning, lateral mobility and quickness is all good to very good. Defensively he gets beat sometimes, but imo not as much as laid out in Brock's assessment for my money. His positioning, especially stick, defensively is very good, seems to know where he should be to defend but still needs to get stronger or learn to use body leverage better to defend at the next level with consistent success. His shot isn't strong enough to be a consistent threat to score from the blueline, but is pretty good at getting pucks to the net through traffic.
I see him more as a puck mover than a true offensive defenseman at the next level, but there is a lot to like there and not too many major flaws.
I think him being a later birthday, pretty average size, doesn't having blazing "beat defenders with speed" top end skating, or a shot that will beat goalies from distance.
I'd be happy with the Leafs taking him with their first. Really strong chance of being at least a really good 5-6 with 3-4 puck mover potential that can QB one of your PP units.