If what you are saying about Matthew 24 is true, then we have some nearly 2,000 year old people roaming this earth. Verse 34 says "Verily I say unto you, This generation shall not pass, till all these things be fulfilled." Matthew 24:1-34 is not in reference to the second coming of Christ. They are in reference to the desctruction of Jerusalem in A.D. 70. Starting in verse 35, and until the end of the chatper, Jesus discusses His second coming. The fact that there are two distinct events discussed in this chapter is evident with careful study.
The Israel mentioned in Romans 11:26 is referring to the spiritual Israel, or Christians. Jews will be saved just like anyone else, by believing in Christ and obeying the Gospel. There is no mention of a mass national salvation in this passage, or any others.
No, Matt 24:1-34 is not a reference to the destruction of Jerusalem in 70 AD. There are some similarities, but it cannot be a reference to 70 AD. There are so many reasons why your interpretation if this important passage is wrong, but let me key on only one aspect.
Verse 21. For then there will be a great tribulation, such as has not occurred since the beginning of the world until now, nor ever will.
This period of time must be a reference to "The time of Jacobs trouble", "the great and terrible day of the Lord", the "great tribulation period". Since there can be only one time when tribulation is as bad as it can ever be, a study of the OT will show that all these terms are references to the same event. The great tribulation.
If that time of great tribulation happened in 70 AD, then the text in verse 29-31 makes it absolutely crystal clear that the second coming must have already happened. And there is no doubt that verse 30 is a reference to the 2nd coming. Notice the "coming in the clouds of heaven" ... just like in Daniel 7! ... In fact, the ancient Jewish rabbis correctly believed that only absolute diety could come in the clouds of heaven. This is why the high priest tore his clothes off his body in Matt 26.63-65. The high priest immediately recognized what Jesus was claiming when He told the high priest that He would come in the clouds of heaven.
Matt 24 is a reference to the 2nd coming ... no doubt about it. And since the second coming hasnt happened yet, Matt 24 is future fulfillment.