Can you explain this idea further?
At face value, this sounds like a bad idea. Incursion matches are already long enough and very defensive. This would make it even worse. Incursion matches tend to snowball after a team loses their first sentry because:
A. There isn’t a huge death robot preventing you from spawn trapping the enemy team.
B. There are two different areas to attack the final robot, compared to only one lane for attacking the mid robot (unless you are playing a character that can jump onto the ledge).
It’s imperative once you lose your first sentry, that you do not let the enemy team occupy the space where the sentry was. Or you’ll most likely straight up lose.
Honestly, the only change I can think of that I would support is to remove the special robots the winning team gets afters destroying the first sentry (the Shepards or whatever they are called) and give the losing team minion advantage. This would help the losing team gain extra pushing power.