I understand why they didn't do that very much: All the set designs and props and new models for space stations would've broken the budget. The reason they did those holosuite stories was because they were easily re-used props from TNG.
If they'd waited until DS9 was done, they'd be able to easily re-use DS9's props and sets for repair station/commerce hub stories and the CGI tech would also have been refined for cheaper easier usage as well.
It was a combo of rushing the show into production, and not hiring a new permanent writing staff from day one (for more consistency), as well as economic reasons, that made the less than it could've been. Not that I'm disappointed but I can at least understand WHY they did what they did.
As for the Borg, I'll just keep reiterating that they should've have a story where they get their hands on a Borg database (or Seven debriefs them) that lets them know that there are different types of Borg vessels with varying power levels and most of the time VOY runs into the smaller weaker Borg ships that are much easier to beat.
Did anyone complain that Jem'Hadar Bug Fighters got easier to beat over time? Did anyone complain that the Dominion had differing types of warships?
They shouldn't complain that a Borg Probe is much easier to beat than an Assimilation Cube, and most of the time VOY fights Probe ships.
And frankly, one of the only GOOD things about the Borg is that they could be used as a plot device to get enemies to unite together to fight them: Instead of focusing on the Borg as the primary, the Borg should be in the background and used as an excuse for VOY to build up a Delta Federation or something. Once they have cannon fodder to sacrifice to the Borg, the show won't get in any trouble for "weakening" the Borg because lots of nameless faceless extras are getting killed until they come up with some contrivance to kill the Borg.
TNG had the Borg kill tons of people and destroy at least two civilizations to build them up
DS9 Had the Dominion constantly killing people to build them up
VOY needed cannon fodder to build THEIR enemies up and to keep the Borg's threat level high. When it's only one ship in trouble and nothing else, you can't take that enemy as seriously as Trek's usual standards.