Learningtofly
You need to be careful when scaling down.
The wing loading is the key factor so its weight has to be in proportion to the reduction in the wing area. To make thing even worse the aerodynamics don't scale well either so it really needs to be even lighter.
For example.
A reduction of span from 44" to 30" or reduced to 64% size. So the wing area will be reduced be reduced by 0.64 x 0.64 = 0.4. To keep the same wing loading the plane needs to be just well under 1/2 the weight. To fly well it should be even lighter maybe just 1/3 of the weight.
So what appears to be a modest size reduction will require some serious care and attention to the construction to avoid creating a flying brick.