To plant a native mix in a 100m block will cost around £5-700 for trees and labour. I would imagine that the cost of bringing in forest residues will be higher, and have a greater impact on the fragile upland soils.
If you are planting hardwood species then the Woodland Trust are offering 60% funding for the trees.
As things stand in Uk forestry, there is going to be a shortage of softwood timber due to lack of planting, i won’t even mention Brexit.
A sensible mix of hard and soft wood will still have a high ecological value, and will also provideyou more importantly a source of income.