They were already halfway to the Delta Quadrant on deep space exploration missions and were also really, really, really fast.
I'd always just assumed the deep space vessels were on deep space missions and that they were starships in the sense that we understand starships, but they could be drones or sleeper ships? But by the end of year 6 Voyager had already past the half way Mark, and besides there's probably still a federation Presence on Cythera which is located near the centre of the galaxy and should really put any relief vessels with in weeks on Voyager by the end of year 6.
By that time VOY had travelled what almost 30-40 000 light years? Remember as well those ships would be heading towards Voyaer so in terms of distance that's another 10-12 000 light years potnetailly. So if it's closer to the 50 000 light year mark those ships would be 20 years from Earth but maybe only 15 years from the Federation border.
Summon space slugs with a magic organ, covert their bodies to energy to superpower their warp drive and get them home in months.... wait...
So in 5 or 6 years they show up.. they don't have any useful provisions for Voyager other than through luck because they are stocked for their own mission. They are presumably smaller vessels with a science geared crew and don't come with any special military might. If they were a lot faster it would make sense to take everyone back and blow up Voyager so no one got their hands on it but I doubt they could fit that many in or provide for them. They could take some people back with them to get home quicker.. but that's not going to help Voyager, it will just deplete them. Are they just going to join Voyager in their journey home as.. escorts? So now we have three ships crawling home over decades two of which could have gotten there faster?
Smaller? These are conceivable generational ships. After 10 years their alone, their crew could double in size if there isn't enough good books on board. And lets remember children make for shit crew, and half the crew would be needed to look after the babies! In Ensigns of Command, they were waiting for a colony ship that was capable of transporting comfortably 15,000 belligerent colonists. Starfleet vessels might be about optimizing their utility, but they're certainly choosing speed over cartable tonnage 9 times out of ten. You're sending a ship out into the unknown (on purpose) for certainly decades, are you going to focus on size, speed or weapons? They don't know where they're going, so it doesn't matter how fast they're going. Their weapons are standard, but if the phasers run through the engines, then a fgaster engine means a more powerful phaser emission, however a larger ship definitely means more phaser batteries. A larger ship also means that they can be economically useful in a pinch when there resources run low. So these ships show up. 10 times the crew of Voyager. 15 times the mass. Yet Janeway promotes her self to fleet Captain and is lating down the law.
Seems to me you'd want a big Galaxy or Sovereign class for those long term missions given they're supposedly the space hotels.
How many people were at your highschool? You knew a lot by name and certainly could pick most of them out of a crowd. Now imagine if there was only a thousand kids and students at your high school? Picard usually had just short of a thousand crew. The primary hull is the merely the size of a few football fields on top of one another. "Bigger" A Federation star Ship is a sprinter, the creature made for a marathon would have to have much much larger fuel despots which might have to be more efficient or even self-sufficient like with how Romulans use stellar anomalies in stead of technology (comparing a hydro electric dam or a geothermal tap, to a nuclear power station.). Or... They could have sent out an ordinary sized ship if the crew was nothing but Vulcans, or another equally long lived species, who wouldn't mind a hundred year long deep space mission... But casualties do stack up over time.
I take it as whenever Barclay appears, the facts just go out the window (might be something associated with TNG cast appearances in other Trek series like "These are the Voyages..."), just like the absurdity of Barclay 'calculating' Voyager's exact position despite the fact they've made six(!) jumps since then. The whole line seems a throwaway, especially since we haven't ever heard much about deep space ships on screen before, just some deep space probes.
We don't know what the deep space vessels were doing, so we don't know how big they were. I always assumed they were taking readings and scanning nebulas and stuff and that they were smaller science vessels.
The Olympia from DS9 The Sound of her Voice, spent 8 years out side of Federation space, charting the Beta Quadrant. Kirk for frakks sake. To go where no man has been before. Archer times that a thousand thousand, in their first month by the time they made it to Terra Nova, it would have taken any other human ship 20 years to play catch up.
Janeway specifically said that Equiinox was too small and rinky dink to handle a deep space mission... And on principles, the season one bible even, so too was Voyager.
They can do any damn thing they want... Cause they got a little 'ole convoy Rockin through the night Yeah they got a little 'ole convoy Ain't she a beautiful sight C'mon and join their Convoy Ain't nothin gonna get in their way they're gonna roll this trekking convoy 'cross the Delta Quadrant Convoy....Convoy.....
If two larger ships did meet up with voyager there are alot of things they could do to help the crew and ship. For one repair damaged areas on and in the ship. Two resupply Voyager with fuel and energy so that the repicaters could make the ship self reliant again. three send a doctor or even a nurse to help the emergency hologram doctor. And any other number of things i did not list here.
If they sent a real Doctor over, he or she would turn off the EMH because that know it all safety net is entirely insulting to the pedigree of their education. Voyager didn't get so damaged that the ship wasn't spick and span the next week. The ship is powered by deuterium(heavy water, Ie tap water shot through a super collider.) and antimatter, both of which are technically and supposedly existing in an abundance in space if you have the patience to refine it from crude.
Starfleet is supposed to be about exploration, so they have ships outside their core territory too, pushing further and further out. The difference being that they signed up for long missions, as opposed to Voyager's planned 2-week Maquis hunting mission.