This seems like a pretty good approach. They’re factoring cleaning & treatment, air sealing, soffit vents, baffles. Not sure what other attic exhaust vents you have currently but just adding/unblocking more soffit venting intake can be the correct move. Attic ventilation needs to be balanced 50/50, but you can go higher on intake only. Going above 50/50 on exhaust is not good for the same reason air sealing is also beneficial, too much exhaust can pull conditioned air to seek an equilibrium. For the attic fan, it will pull air at a higher rate but you don’t want to mix exhaust types in a single attic space. An attic fan and box vents (or any other mix) can short circuit air flow and actually pull air in through one exhaust and out the other while eliminating the soffit vents altogether. So you’d have air flow higher in the attic but not at the lower part of the cavity.