As I said, you need to learn more about the classification of living organisms. All multiple celled organisms are eukaryotes. All fish are eukaryotes. All amphibians are eukaryotes. All humans are eukaryotes. The classification of “eukaryote” is very close to the
root of the Tree of Life. At that level the classifications are: viruses, eubacteria, archaea and eukaryotes. All of those classifications contain multifarious species.
Unless you are going to dig into the real differences between the different strains of bacteria and the different strains of viruses then your illustration is worthless. You are mixing classifications at the highest level (viruses) with classifications at the lowest level (species). At the level of your virus example there is no difference between a fish and a human, both are eukaryotes. If you want to make your example relevant then you need to look at how different viruses evolve from each other, and compare that to how different eukaryotes evolve from each other.
This is plainly incorrect. Now that we have been able to sequence genomes we can see that there is an immense amount of variety in bacteria (eubacteria and archaea). There is less variety in phenotype but there is a greater variety in genotype. Viruses are even more variable as they lack most of the error correcting mechanisms present in other organisms.
rossum