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Hi Andre
As genus is a latin term, the plural is genera, rather than genusses. ;)

As for systematic arrangements of species, the old British Checklist was organised on a systematic basis, but there were so many arguments about the exact placement of genera and species, and everyone found it diffficult to use, that it was decided to stick with an alphabetic arrangement.
This has several advantages -
1. It's much easier for a beginner (and most experts!) to find things.
2. It doesn't change as new studies discover different relationships between genera.
3. It doesn't mislead you into false conclusions about relationships. After all, the relationship between genera and species cannot be described in one dimension. You need at least three (if not four) to represent relationships accurately. A systematic checklist (which is one-dimensional) must obscure some relationships as it shows others.

The disadvantage of the alphabetical list is that if a name is changed, the species' place in the checklist changes, but it's just as easy to find the new name!
You may have good reason to want a systematic arrangement, but I wouldn't spend too much time searching for the perfect one, because it doesn't exist! :(