First, other reviewers are wrong that the show started to go downhill from here. The mere fact that it belongs to the Stargate series is enough to warrant the downhill rating, and the reason is simple: apart from being a rip off of other series and the occasional grandeur and attractiveness of the main plotline - i.e. Excluding the many filler episodes - regarding the "fight" against Goa'uld / Replicators / Ori / Wraith / Genii / Assurans (I say "fight" because the "bad" enemies somehow always spare the lives of main team characters, while the latter always seem to "win" through some overused but unrealistically effective guerilla tactic, not to mention always taking the fight and life and death situations lightly), each episode is basically the main team fixing the disaster caused by their own crew's incompetence, disobedience and stupidity in the last minutes of the episode.
This is where this episode actually does the right thing, albeit to an undeserving (but only if you count this episode off) and otherwise likable and funny character: finally, the incompetence, poor decision making and disobedience of a main character is rewarded with the realistic payback for that person: death. I won't spoil other details, but once you see this it becomes clear that, in this episode, the eliminated character:
- severely endangered the whole Atlantis crew for a single individual
- blatantly disobeyed common sense orders conveying the above
- insisted on handling things instead of much more qualified crew members
- acted out of character by placing individual good above the common good
For those reasons above alone, the eliminated character deserved the outcome, so good riddance. The problem was not with the character itself however, which was one of the few that actually was OK in most aspects, but with the choices the character made (yeah, the abysmal writing, I know). By that standard, almost all the characters should deserve and logically be subject to elimnation, but since most of them are there just as cliche bait for the viewers (e.g. The good guy, the annoying one, the brute and the woman - I'll let you figure out which is which in both SG1 and SGA) it isn't feasible to do the logical thing and make them pay for their own mistakes.
That being said, SGA was at its beginning much better than SGA, simply for the fact that it didn't seem to make the same mistakes: base being conquered easily each episode, trying to be funny without being funny at all (I'm looking at you, O'Neill), moral questions sabotaging the natural outcome of a situation in critical moments, being more concerned about making jokes and exploring empty forests and petty villages than surviving against so called mortal enemies (NID was actually right on that one), and so on. Unfortunately, these mistakes slowly came back to haunt SGA as well, probaby because the poor writers were assigned to SGA after SG1 finished airing. At least this episode, despite the poor writing and similar decision making of a character, provides a logical and natural outcome. Too bad it wasnt done for the sake of realism and proper story telling, but only to make room for other characters and recycle this one for the following seasons on in the series (you'll see what I mean later on).