Paul is very clear in teaching that we have to give financial support to those dedicated 100% to our service. There is not doubt on that. The curious think is that even teaching that, he still has not a single word on tithing. Yes, Paul teaches that we have to be responsible for maintaining those in our service, but never ever by tithing.
That takes us to the next two issues:
As Christians we are free to do what ever. I can drink a cup of wine, I can go to a rock concert, but if for my brother that is an obstacle, if he is not enough mature, I shall give up my freedom and stop drinking wine and listening to rock and roll.
If you are mature to give to your church and pastor some money, if that is not really tithing in a camouflage, if you really are not tithing, if you understand that tithing is not one of your obligations, then you can do it. But still you have to care of your brother and see how it affects them.
As you can easily read on this thread, there is many brothers that believe that tithing. They believe that still have to keep the Law. For those brothers, you are setting a bad, very bad example. You shall commence immediately to convince them that tithing is absolutely wrong. That is the first and most important thing you have to do.
Otherwise, your argumentation is just another attempt to keep on teaching tithing by trying to foolish God.
The second issue is to check out who are we supporting. Paul said that we have to exam our pastors. Firstly we have to see if he/she is a pastor on the meaning of the NT, or if he/she is a pastor in the modern meaning. Being graduated from a seminar, having a diploma, being hired to take charge of a local church, is not what a pastor is.
If we read Timothy and Thomas, we found out that a NT pastor is somebody in your service. A NT pastor serves the brothers.
A pastor that serves his/her denomination, that is an employee obliged by a higher administration, is not at our service. It is not possible serve tow lords. Eventually the high administration and a specific congregation will enter in conflict. On witch side is the pastor?
Suppose the high administration is implementing a national evangelical program, or is sending a missionary to some country; if the pastor is implementing those programmes into the church, he/she is servicing the administration. He/she is imposing something to the brother that actually is supposed to serve. He/she is acting as the boss, the one in charge, the authority, not the servant.
Think out. Your congregation is sending a mission to Uruguay (my country). They said that it is an evangelistic effort. I have news for you. In Uruguay we know about Christ since the Spanish conquer. Also we have hundred of protestant denominations: Mormons, Witnesses and many Evangelic. Probably we don’t have yet one of that denomination. That means that your denomination is actually in an effort to open a new branch in a territory where the Gospel is widely preached. Don’t get confused: the evangelic efforts are merely an expansion of a denomination.