Low-scale supersymmetry

Question

One of the major reasons SUSY was adopted in particle physics is to Naturally have a Higgs boson (a fundamental scalar) at the weak scale.

If we abandon this argument, what other motivation for low-scale ($\mathcal{O(1)}$ TeV) SUSY exists?

Answer 1

Some other "basic" arguments in favor of SUSY also prefer TeV-like superpartner masses although not necessarily as light as 1 TeV.

The dark matter composed of neutral superpartners, to agree with observations of the current amount of dark matter and the required amounts in the cosmological past needed to preserve some important cosmological processes, should also have mass at most several TeV, say at most 10 TeV.

The gauge coupling unification – which may exist in Nature because it's elegant but not it is not inevitable – in MSSM works with a satisfactory precision but only if the running is dictated by the spectrum of MSSM on "most of the logarithmic interval" between the electroweak scale and the GUT scale. Well, here the tolerance is clearly higher for higher masses. Also, one may imagine that some corrections or modifications of the spectrum do the job despite very heavy superpartners. But the simplest MSSM-like way to achieve gauge coupling unification, which still looks intriguing to most physicists, also has to assume that all the superpartners are much closer to the electroweak scale than e.g. to the GUT scale.