Shinra's descendants establish the Shin-Ra Company on another world (FFVII's world) thousands of years later. This is explained in a couple of the Ultimanias. Cid Highwind's Shera airship belonged to the Spiran settlers. These aren't really loose ends.
The Farplane's instability in X-2 was caused by Shuyin, if I recall correctly. His malice warped even the fayth when they went to stop him.
On the issue of VII you can’t compare it to X in regards of a concluding the story because it was done in Advent Children. Square went off on some wild tangent in Dirge Of Cerberus. Also, and I think many share my opinion; Square Enix (not Square) has all but ruined Cloud. I don’t know who this whining, brooding emo poser is but MY Cloud dressed in drag, went on awkward dates and said “let’s mosey."
Well, regardless of your personal opinion of Dirge, Genesis or Crisis Core, the fact remains that the story is incomplete while X's was perfectly wrapped up with no loose ends.
As for Cloud, he was neither whiney nor emo. He did the opposite of that. Whiney/emo people ***** to anyone who will listen and tend to complain incessantly about inconsequential bull****. Cloud shut himself off from the people he loved, whom he felt unworthy of, while he was dying and unable to find a cure for his dying adopted son. He was faced with those crushing developments while trying to recover from the survivor's guilt he felt regarding two other people he loved whose deaths he blamed himself for.
He didn't share his feelings with anyone until Tifa blessed him out, so I don't know where you're getting "emo" from. Advent Children depicts the last day in almost two years of emotional anguish and soul-searching.
And if you don't think being terminally ill yourself, feeling useless because you can't help your terminally ill child and being wracked with guilt over two other people you love being
dead are valid reasons to brood -- well, I don't know what to tell you. It's going to be pretty impossible for us to have a constructive conversation if those emotions amount to being "whiney" in your eyes.