Firstly you have to demonstrate where the virtue is in taking this line since it assumes that everything that is is revealed by this method. That assertion itself is not revealed by the very method it advocates to establish validity. It is time then for one of you to establish the virtue of your assertion.
No, because it's not precluding other systems, it's not saying this is the only way, it's saying if you want to propose another way then it needs a similarly robust justification, or it can be ignored.
As I have said before, observation is no longer a neutral act and therefore that which is affected by observation is contingent.
But the reasons that you give for holding that view aren't convincing anyone.
The law of sufficient reason logically proposes a necessary as sufficient reason for the universe.
Which is begging the question in the first place. We have a universe, yes, but there's nothing in there to show a reason to think that this universe had to happen.
That necessary reason cannot logically be a contingent and so even if you propose that in some way the universe itself is the sufficient reason you have to find what that necessary thing is.
Given that the evidence available suggests that time, as we understand it, is a facet of this universe, and came into being with this universe, then ideas of contingency outside of this universe and causing it don't necessarily follow the same rules as the contingency within the universe. There is no 'before' or 'after' outside of the universe where our time does not exist.
Unfortunately the atheist cosmologist Sean Carroll declared his intention to try to find a loophole in the principle of sufficient reason and Bertrand Russell just baldly avoided it where the universe was concerned.
I'm not familiar enough with either of their works to comment.
So on balance saying that the universe just is and there's an end to it(Russell) or suspending sufficient reason in the case of the universe(Carroll) is special pleading and looks suspisciously like sufficient reason for the universe dodging or even Goddodging.
No, it's not special pleading. If you want to claim that the 'purpose' of reality is our universe you need to justify that. Yes, there's a case for coming up with a sufficient cause for the universe to explain where we come from, but there's no need to try to find a necessary cause until and unless you can justify the claim that we are necessary at all.
Again if you want to please show the virtue of the Russell or Carroll positions.
As I said, I'm not familiar enough with either of their works to know if this supports or is parallel to their takes on things.
O.