If Kawhi is really going to stay, I'd bump it up to Brown + Smart and dare them to do better. Maybe hold a draft pick in reserve.
If we're *not* paying Brown or Smart, there's a future state where we basically have our Big 4 deals (Irving, Hayward, Kawhi, Horford) plus the entire roster on rookie or smaller deals (Tatum, Yabusele option, Ojeyele option, Rozier RFA, Williams, '19 picks).
Baynes, Morris, Theis and Wanamaker all 1-year bridges before the new deals.
Especially if Horford works out a new extension, it's doable $$-wise compared to what CLE and GS have been up to lately.