How could gravity of any force hold everything in place with great precision with such enormous vastness of empty space/ vacuum ?
What makes you say it is great precision?
Your statements about Pluto indicate it isn't that precise. It is in an elliptical orbit.
If you look at the Earth, it's orbit isn't even an ellipse. The moon perturbs it so it is wavy, and it gets disturbed to some extent by other planets.
Geostationary satellites are another example, where constant station keeping is required to keep it in position with all the perturbations.
It is like imagining that we can blow a balloon without exploding to the size of our Earth.
No. It is nothing like that. A balloon is made of material with a certain tensile strength.
As you expand it, you stretch this material, reducing it's thickness and thus increasing the stress on the material.
Eventually the material gets too thin, with too much stress and breaks.
Sure you can say use a thicker balloon, but then it requires more force (pressure inside) to be able to expand the balloon and thus you get the same problem.
Space and gravity is nothing like that at all.
Gravity is merely distorting space time by bending it a bit, more akin to putting a weight on a trampoline or sheet.
Not even mentioning the speed of spiral arm gallaxies that defies this possibility even more.
How?
What is the current plausible explaination for this ?
Explanation for what? I see no problem so far?
Can we really observe quadrillions of miles looking towards the boundaries of space ?
Yes.
Light will continue to travel unless it falls into a black hole or is absorbed by something.
So unless something is in the way we can observe it, sometimes we need more sensitive instruments than our eyes, and/or really long exposure times.
It seems so convenient, because there is absolutely no way to verify anything, not even in the scaled down cosmos, which still has absurd distances that would make you wonder about the "real" cosmos/ distances.
No. You can verify things.
For example, you can verify various distances on Earth, and positions of things, and timings of things, and then verify that the sun rises due east and sets due west on the equinox, requiring it to be very far away.
If you allow up to a 1 degree margin of error at the equator, and then construct a right angle triangle to determine the position of the sun (with a distance of 10 000 km between the equator and the north pole for the FE model), you end up with the sun being over 500 000 km away (up to an infinite distance).
In order to match the FE model, you need an error of 45 degrees at the equator.
It gets completely impossible in the southern summer as the sun is in the wrong spot.
So yes, we can verify things, like the sun being very distant. We can then use that fact, along with the sun travelling over the equator during the equinox, to show Earth is round.
And then it is calculation after calculation using various things (and observations) to determine scales.
Yes, the universe is big, and we are tiny and insignificant. That doesn't make it false.