Until it doesn't make sense anymore. Until we get a franchise QB, this should be priority no. 1 - getting a player that can be our franchise QB. If we are not getting the franchise QB now, we should be accumulating future assets to help us get him next year. Also, those trades actually make sense value-wise in most cases.
No you don't. He's getting value out of those trades. He's done REALLY REALLY well with the value of those so far. Until there are teams willing to give you that value you should be making those trades. (that's generally - in some rare cases you might have a player on your board that you think is worth more than the return, in which case you make the pick.
That's not exactly the case. The value of low 1st is about the same(slightly higher) as the value of early-mid second. So if you can trade 26 for mid-second + another second, it makes perfect sense to do that trade. The dirty little secret of the NFL is that over the long haul there isn't much of a difference between NFL front offices in their pick success and the way to succeed is to acquire multiple picks in similar, although slightly lower range. In the most simplified way I can explain it - it's better to have 2 picks with 45% success rate than one pick with 50% success rate.
Again - disclaimer - in rare cases where you have a player that you value much higher than the picks you would be getting, you have to take the player and refuse the trade. Also QBs are so much more valuable than other positions that they too require their own special set of circumstances.