I don't think there needs to be a massive overhaul, though it would be 2 large positions filled, I think there needs to be 2 hires.
European head - Sens have legitimately not hit on a player, outside of Stutzle and Zib who were top 5ish gimme picks, taken out of Europe in 15 years. Silfverbeg and Lehner in 09'. You need to have some european talent coming into the league, you need a viable presence in Europe and Russia, it's ~50% of every draft class, Sens have essentially eliminated that pool, and when they've gone there, they've reached for tools, which we know is something they value, a large majority of the time. It hasn't worked out well.
New Head of Amatuer - Sens have 3 guys who have been scouting for them for a combined 65 years in Fargher, Janecyk and Boyd who carry the room. Sens need an outside hire to slot in above these guys, otherwise we are going to continue to make the same selections we've been accustomed to so much people can accurately predict who is being taken where hours before the pick
Like the Leafs bringing in Leach to be their Head, their drafting is going to see a very large detour from what they have been doing the past 5+ years, the Sens need the same kind of influx