Great article and analyzation of those relationships.
Love it, and totally agree. Yes, that and Spike and his development is what actually makes the whole series worthwhile watching, all others are side figures – arguably in parts quite important, but they are all entourage. Angel as a character is actually quite weak (opposite of Spikes forceful demeanor) and Xander, don’t get me started on him – how many times did he want to stake either Angel or Spike, out of selfish reasons, fear at the minimum, but constantly masquerading it as thoughts of friendship for Buffy and her safety?! Yes, at times he did stand up and did what is right, but in many ways he was a weasel.
It’s a bummer that there will always only be one Spike. Have mercy on the day when somebody will try to do a remake or a movie ‘continuation’ with another ‘Spike’.