The Germans can pretty much “hasty attack you to death”. The additional loses prior to Sept 1st, the bombers, artillery, Commander roll for Germany and the failed roll by the Soviets combined to make a bad day for that Soviet Division. What can you do about it? Not much. Even note the 2 engineer factor reducing the fort to zero. You would think the Soviets are a bunch or “Morons” looking at this combat result.
Are you in any doubt? Of course the Soviets are morons led by an even bigger moron. That dude sitting behind the keyboard controlling their every move is more Pavlov than Zhukov if you ask me.
The main purpose of leaving the division there was to slow down the Motorized Division in crossing the Dvina river (the two divisions were adjacent but on either side of the river). As the Germans spent MP to actually do the attack, from that objective the fight was a success.
The secondary purpose was to see if the German mobile divisions attacking swamp hexes would take casualties higher than normal. As it turns out, virtually the only battle cost for the Germans was to their stores of ammunition, as they had to shoot all those Ivans.
The question is if I paid to high a price in casualties. I probably would not do the battle today, if I had the same choice knowing what I know now, but that's a process I refer to as "learning" :-)
Oh, I am in no doubt that the Soviets are Morons. But don't be hard on yourself, you are very capable player.
In your 2nd paragraph you hit exactly why I would do it again. But I would put the PM divisions(if they were available) in that hex instead of a decent division. You will take more loses but why not? You will do about the same amount of loses to the Germans but take a couple more hundred loses yourself and serve the same purpose.
In your 3rd paragraph, don't get your hopes up on causing any higher loses this early and against Moto units.
In 4th paragraph, I don't think you paid too high a price (although I think the loss rate is lopsided personally). I would recommend you still do these defense battles to burn up German MPs in the right places. I know I took on another game and I am forcing the Germans to burn through MP's by staying close. I am losing a lot of units but, as you mentioned, it is burning German ammo, fatiguing them, and a few other things. Which in turn causes them more loses.