There you go-- good point. Mind-bending stuff. When, on a show, and they go to a planet, I want to see some aliens. I want something completely alien to what I see around me 24 hours a day- it's an escape. I get enough drama and such in real life. Don't need to hear about a crewmember's love life, or how hard their working, or how their cancer is doing. I want monsters, explosions, time travel,heroics, talking slime-blobs, kung -fu wise-cracking robots, etc.
then you were made for Farscape :D
Ahhh now i see why you don't like the new BSG. Ron Moore was sick of doing "alien of the week" stuff with Star Trek, one of the guiding ideas of the new BSG is no aliens. Doesn't work for everybody, I happened to be with Moore though I thought constantly throwing in new aliens had made Star Trek pretty boring.
Starship Troopers is one of my all-time favorite sci-fi flicks. I could enjoy the background social commentary and laugh my @ss off at the boot camp antics, all the while being awed by the superb CG visuals of hordes of alien "bugs" going gun-to-claw with the Mobile Infantry!
Denise Richards was icing on the cake! :)
The big problem with a lot of sci fi is the alien with the different bumpy pattern on its head. They were basically human with different facial features. SG-1 has done a reasonable job of coming up with interesting aliens. The G'ould were a cool idea when the series first came out. Replicators were good, too. ST:TOS was OK with it, but still cheesey. The newer ST's were really bad. Babylon 5 did a good job with aliens, but it wasn't the visit a new planet every week type of thing you are thinking of.
One of the big problems is that things that are really, really alien don't necessarily make the best TV. If the story isn't compelling, it won't get a strong fan base. That idea can work well but it can also get tiring. Plot and character drives the storyline which is why so many people here love the new BSG. But if you just want to see things blow up, or want a weekly creature feature, BSG isn't for you. Another pitfall that I don't like is the alien = stereotype. Star Trek was, in my mind, notorious for that.