Here is a model that might get you many features you look for. Imagine a balloon.
Imagine the surface is expanding. If it is like bubble gum then as it expands it gets thinner and expands more easily, and it could pop. If however you had some objects free to move around the surface but attached by springs then they might slow the expansion and even make the whole balloon slow its expansion, eventually stopping, and then contracting until it all crashes together (don't imagine the balloon as having air in it, just parts that were all rushing away from each other). Maybe it was made out of rockets that all shot away from a common center with a big explosion and then we just cruising outwards with some velocity.
OK. Not what if time was the radial distance from the center. Then at every moment you have a different sized 2d space and whether it will expand forever is really a function of how strong those springs are compared to how much it was expanding outwards.
That model isn't entirely accurate. Among other others things you'd need a 3d surface in 4d spacetime. But you see some features. Firstly, each point looks the same as all the other points at the same time. Each sees a universe that is expanding. And it is expanding into the future, not into some larger space. The current universe always becomes the future universe and there is room in the future for the universe to be larger and every point can look the same.
When you have too few springs things fly apart forever and when there are too many it eventually slows how fast it expands. And there is some magic critical amount right between the two.
Out universe has regular matter attract things to it, much like the springs. The universe is expanding but the matter acts to slow that down. But we see things expand in a way as if we are really close to that cut off. And we don't see enough matter to explain that.
So we think there must be more matter we can't see that makes it be like that. And it's nice to be like that, the universe can get large enough to have interesting things in it but not have everything so far away they can't see each other. If you lived in the balloon and tried to send something around the balloon to your friend that also lived in the balloon then the thing you send would have to go to the future (everything is going to the future). So you could mark the point halfway between your friend and you and so if the balloon got so large by the time that your message got to the original halfway point that the halfway was now farther than you friend originally was and it keeps expanding fast enough to make that happen then your message is never to reach your friend.
So expanding universes have regions that can never communicate. And we have some evidence that our universe might have something like an antispring that makes regions without springs (mass, regular energy, momentum, stress, and pressure all act gravitationally like springs) expand faster and faster. And since it makes more empty space and the empty space has that property, it is a long term win for the dark energy.
We don't really know much about dark energy or dark matter, the dark matter acts normal but we've only ever seen it gravitationally and don't know what it would be made out of. Dark energy is even less well understood.
Now an important thing to note is that in regions with more springs than average the space could not expand even if in a large scale it does still expand, and the things that set the sizes of things ate the interactions between the parts. So any effect of expansion has already affected the size of things. Just as any size of contraction. For instance the earth is smaller than it otherwise would be because it is attracting itself together we don't need to throw that in one top of other effects.
So you are already seeing the things be as close as they are because of all the effects.
In the regions between the galaxies the density is lower than the critical density so they will get bigger and dark energy could make them get even bigger in a run away fashion. Regions with a critical density will not be getting bigger in a run away fashion and if they are greater than critical density they could slow the expansion in that region.
