This is really a taste/preference thing. Personally, I like the current print-up-to-three behavior; I often find three is used as a cutoff before eliding in many contexts.
If you just have a handful of commonly-used long types like that, you could export them from your package and then printing will use those shorthands:
julia> import BlockArrays, ArrayLayouts
julia> @eval BlockArrays begin
const StepAxis = BlockedUnitRange{ArrayLayouts.RangeCumsum{Int64, StepRange{Int64, Int64}}}
export StepAxis
end
julia> T = BlockArrays.BlockedUnitRange{ArrayLayouts.RangeCumsum{Int64, StepRange{Int64, Int64}}}
StepAxis (alias for BlockArrays.BlockedUnitRange{ArrayLayouts.RangeCumsum{Int64, StepRange{Int64, Int64}}})
julia> Tuple{T,T,T}
Tuple{BlockArrays.StepAxis, BlockArrays.StepAxis, BlockArrays.StepAxis}