Gates are wideley spread in every doom map, whether the standard GATE flats in combination with the SUPPORT3 is used or if they are metallic/spacey with lots of SILVER and SHAWN. But most of the time, not much time is put into these teleporters, usually it's just one sector so there is not much space for detail, isn't it? However, there is space! Think about the reality: If we would already have teleporters, they would be much larger, because they are very complicated constructions, lots of technique and/or hellish material. This is where we start to develope better gates!
In shot one you can see a very simple advanced space-gate, a bit larger then their originals. I haven't done that much to this, I just added a border and 4 steps around the teleporter, but as you can see, it looks much better, better then a teleporter with just one sector could look. (buildtime 2 extra minutes)
In shot number two I developed another method to build up a interesting detailed gate. A huge border (with 8 corners) was added and over this border, 8 pillars of COMPSPAN and CEIL5_1 continue over this SHAWN-y construction. The result is beautiful and the new scale of the teleporter makes it much realer! (buildtime 6-8 extra minutes)
Shot three shows off the teleportergates you can see at the beginning room of "The City Of The Damned", this time I used a normal GATE flat in combination with lots of METAL and some SLIME metal floor parts. This one is almost the same as the gate shown in shot 3, just altered a bit. And don't forget the little extra detail, the particle fountain (always make it the same color as your gate floor when you work with ZDoom) (buildtime 6-8 extra minutes)
The last shot number four shows another small teleporter-gate variant, this time it's base is a COMPSPAN/CEIL5_1 combination, hold by planed metallic SHAWN pipes. Although this is also one of the easier gates, the slope effect does a very good job concerning the visual detail. (buildtime 2-3 minutes extra)
Summary: Gates were used consistently in Doom maps but most of the time, their full potential wasn't used. Design your gates wisely, scale them into larger dimensions and gain a feeling of reality for the players, and don't forget the additional sectors and linedefs for your statistics :)
Extra-Buildtime: "2-8 minutes" (depends on size of the gate)
Build-Difficulty: "Low - Medium"