To me what also acts as 'proof from God' besides 2 Timothy 3:1-5; Luke 21:11 is what Jesus said would be done at the same time as mentioned at Matthew 24:14; Acts 1:8.
In connection to all that is happening on an international scale is also coupled with the declaring about God's kingdom of Daniel 2:44 on a world-wide scale.
This proclaiming about God's kingdom government is now a direct link being done on a grand scope as never before in history.
Modern technology has made possible rapid Bible translation so people even in remote areas of Earth now have Scripture in their own mother tongue, their own native languages. This includes audio and video.
Yes, MAN has dominated MAN to MAN's hurt, to MAN's injury - Ecclesiastes 8:9
So,this includes those in power over others controlling this unrighteous world. ( this includes corrupted political, religious and business power )
When Pres. Johnson was Senator he said 'who ever has the ultimate position has the ultimate power', (thus the space race as part of great signs in the heavens, plus including the 'governmental heavens' lording it over mankind in general ).
However, corrupted mankind ( some who think they shine bright like *stars* ) they ignore that the God of the Bible has that ultimate position.
Theinternational telling about God's kingdom is now in its ' final phase '.
So, this means we are nearing the ' final signal ' as found at 1 Thessalonians 5:2-3.
When the powers that be will be saying, " Peace and Security...." this will prove to the the precursor of the coming great tribulation of Revelation 7:14,9.
So, to me this is Not vague but comprehensive that the God of the Bible will soon have Jesus take action - Isaiah 11:3-4; Revelation 19:14-16
I don't really have a motivation to argue these points as you started off by saying "to me" and I don't have a problem with people having their own opinions and recognising it as such.
Regarding the direct link: my viewpoint would be that there is preaching being linked to an ancient scripture, but I don't see the link as relevent, as other groups, like the 7th day adventists, also preach about Daniel 2:44.
Regarding the signs of heaven I had an interesting conversation with MJFlores about the signs. It was presented that the the great sign in heaven is a reference to the day that the sun was actually darkened, as it was a dark day, which is New England's Dark Day which occurred on
May 19, 1780.
To me this stuff does seem vague and ambiguous or too normal because there are many different interpretations out there, like with what "great signs in the heavens" means, and some of these points are just not exceptional.
Someone preaching and speaking about Daniel 2:44 has been done already.
Bible translation is an exceptional point, as others haven't done it on such a scale, but that is not a fulfillment of prophecy.
Ecclesiastes is a general statement about the world which was even true in the writers day, as he was writing from observation.
The great signs in the heavens is a vague statement at which a person can connect any "heavenly" event to and interpret it in various way depending on what they wish to emphasise.
The last days point is also controversial. According to Peter, the last days was in effect from the time they received the Holy Spirit (Acts 2:14 - 39), so the obvious reading would be that the Book of Acts says that the last days already started back then, which would mean that people are still waiting 2000 years later. Will the final signal ever come or were they talking about stuff that would never happen? (rhetorical question).