Regarding the discrepancies in characterizations--watch
any show that's run for four or more years. You'll almost always notice that the characters don't become the people you "remember" until about Season 3. That's also the season where most shows start getting really good. (And yes, before anyone decides to clobber me with "what about this show?" and "what about that show?", yes, I know there are exceptions, I'm just speaking generally.) We talked about this in my intro to Electronic Media class last semester. It was something I kind of noticed over the years of watching (too much) television, and it was kind of interesting to learn that there was something to it. It usually takes the writers and producers a couple of years to really figure the show out themselves. They keep what they like, throw out what they don't (generally because they believe the audience doesn't like it that they could be losing advertising revenue over it) and invent some new stuff to replace it. They don't count on you noticing it when they change or do something inconsistent, and most times while the show's in production, they're right--it's harder to catch these things when you're only watching once a week over the course of several years. But as soon as you start seeing reruns, maybe shown daily in syndication on another channel, and start buying box sets of DVDs, and can start seeing these things a bazillion times in fairly rapid succession, that's when these things become glaring and sometimes annoying.
But generally, if you look back at any long-running show, Season 3 will generally be where its "peak" begins, and the characters' personalities will be established pretty consistently from that point on.
Hoshi is an interesting example. I remember when I watched the premiere way back when, I called my mom when it was over to ask her what she thought. I remember my mom saying she really liked Hoshi because she was the "regular person", not acclimated to space travel and all that stuff. Jumpy at the strange sounds and sensations...and later "the stars are going the wrong way", etc. But, you could see how after a few episodes that would get old. What was initially interesting and relatable about Hoshi had potential to become annoying and boring. You can't have her complaining about space travel and blowing her groceries into a space sick bag every week for however long you expect your show to last. So, she becomes a black belt, who should've been able to break that Suliban's arm in Episode 1.

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