The funny thing is, I was very excited about Voyager when it first started because I assumed by its nature that it would be a serial. I thought the ship design was very cool. I loved Jerry Goldsmith's theme music! The opening sequence was beautiful. But then, the story didn't go where I thought it would. I was expecting more conflict on the ship. I was expecting a story arc that would, say, leave them stranded on a planet for a few episodes, have the crew split up at some point (Maquis & Starfleet) and then be forced to come together episodes down the road. Anything like that with a little more risk would have been ideal for the show. I stopped watching shortly after 7 of 9 was brought in -- so I do still need to give Voyager another chance through my awesome Netflix subscription. But anyway, I think it's funny because the one thing I wanted in the show I was watching at the time (Voyager) is exactly what was happening in the show I was completely ignoring (DS9).
Your expectations were way out of line with Star Trek and television then. In 1995, that level of serialization and being set away from a staple (in this case the starship) was quite rare (outside of soaps). Networks didn't risk it. They had a (misguided) notion that most of their viewers didn't
see the previous episode or indeed at least a dozen of the past 2-3 dozen episodes. They felt continuation would deter viewers unless it was from a tight, action-packed story with a cliffhanger (e.g. a 2-part story, season finale cliffhanger). Syndication wasn't arc-heavy either. Xena's Dahak arc & Twilight of the Gods was quite loose, Hercules' Dahak/travel Europe arc was as well.
Even DS9 didn't start to do close running arcs (and even then the episodes had very distinct identities. i.e. no one will confuse "Rocks and Shoals" and "Sons and Daughters" or "When It Rains..." and "Extreme Measures") until 1997-99 and in the first case, they still showed the station by having some cast still on it (Odo, Quark, Rom, Kira, Jake). Babylon 5 was doing it, but it didn't get heavily serialized (deep into its arc) until parts of Season 3 (95-96). Season 4 (96-97) was heavy, one arc after another (Shadow and later Shadow-Vorlon War, Minbari Civil War, Earth Civil War), Season 5 got heavy in the back half, though there was a smaller Telepath arc early in the season. DS9 did remember
its past episodes though. Most of the series wasn't serialized. Serialized shows took off in niche venues, like cable channels. B5 & DS9 bucked the trend. X-Files did a little too, even though other than introducing elements (syndicate, black oil, etc), its mythology arc had a short-term memory and was just adding to the mystery, rarely ever solving it (it had the illusion of continuity). It would be hard for Paramount to produce multiple episodes of Voyager for a network, or even syndication where Voyager is nowhere to be seen, even if a recreation, impersonation, whatnot ("Living Witness", "Course: Oblivion") or where a bunch of rebels commandeered Voyager for more than part of 1 episode and it took 3+ episodes to get it back. "Basics, Part II" only had the Kazon in control for most of the episode and the takeover was part of a cliffhanger so everyone would expect a resolution by the end of Part 2. And the Hirogen takeover, the entire crew was still on the ship, it was just occupied.
Look at it another way, even besides networks not liking heavy serialization, production studios might be risk adverse, particularly since there wasn't much precedent, and soaps had a rather trashy reputation, at least from the perspective of writers. Until arc pioneer shows proved themselves, many shows wouldn't touch an arc.
And yeah, Voyager's opening is excellent. It still looks beautiful and sounds wondrous 17 years later. I think that gets ignored. It hands down had the best sounding and best looking opening of *any* Star Trek series. DS9's wasn't bad, but it felt like it was missing something from making it great and the rather unremarkable background/visuals made it no contest (the big wormhole reveal was all it had going for it there). TNG sounded a bit pompous. DS9 sounded dignified (definate airs of that Olympics theme and some other work I think from the '40s. By Copeland?). Voyager sounded majestic and wondrous and looked the part too.