Christian,
I can sympathize with your confusion!
Understand that I am not saying there are no examples of "true" species. There are valid grounds for assigning species rank to many of the South African taxa. The problems begin when individuals become seggregated from their populations. Once this happens, there is no way to be certain it has no hybridogenic involvement.
Most of the forms I grow do come true from seed: that is, they produce identical plants in the F2 generation. Hybrids may become stable over time: this is all part of the process of speciation.
The problems with introgression are what lead Dr. Schlauer to be very reluctant to grant species seggregation to species novae publications within the South African taxa. Paul Debbert has repeatedly tried to publish new species from South Africa, but these attempts have usually been discounted, and this is the reason why.
Some have argued that gene studies will resolve the issue, but it must be remembered that phenotype is not dependent on the presence or absence of a single gene, but rather from the interplay of many genes. Studies involving L-ribosomal DNA markers are useful, but not definitive.
Once I thought it would be a simple matter to photograph and record the some 130 Drosera species out there, but I soon came to realize the complexity of such an undertaking!
There are no real answers, only opinion when it comes to these plants. I have grown CP on and off all my life, and I am very familiar with the genus Drosera under cultivation. Only after talking with Robert Gibson and Jan Schlauer have I become aware of the great difference between cultivated plants and material from the field. Herbarium and field studies go a long way toward understanding the dynamics of these populations. After leafing throunf many herbarium sheets, understanding becomes more defined, but IMO never absolute. Taxonomy is a very artificial system designed to make sense of a process that our senses can never apprehend. With the South African taxa, it will always be a best guess, no matter if it is Dr. Schlauer, Robert Gibson, you, or me. I think you have a good grasp of Drosera, and I think you can trust your own impressions regarding these plants
I will be happy to provide you with my personal opinions regarding your plants, but be aware that they are personal preferences based on a very limited experience of what is really out there.
The good news is many Drosera species are better behaved than the South African taxa, and are distinct species with differing karyotypes, and incapable of producing fertile seed.
(at least until Ivan Snyder came along, LOL>)