It seems like you're separating "TV series Spike" from "After the Fall" Spike, whereas I'm saying separating out "After the Fall" Spike is akin to separating out "School Hard" Spike or "Crush" Spike. Of course you're not going to get a full picture, because you're only looking at one of the pieces. You said it yourself - "he looks different in different situations." ATF is only one situation. It's not really fair to hold up one limited-run comic series against seven seasons of television and say, "TV Spike is way more complex and developed than comic Spike." Of course he is - he had many more years of being placed in different situations, and many more different perspectives provided by a multitude of writers.

While ATF Spike certainly doesn't cover every facet of his personality, the ones it does address don't seem to be out of character or contradict what we saw of Spike on the show, so I don't understand the need to divorce the comic version from the TV version in summarizing him, any more than you would try to analyze season 8 Buffy without considering her character in seasons 1-7.