I agree with several of your points - however, I do disagree in that I don't see us going to many 3-4 receiver sets. That's just not our style, doesn't fit our run game or the skill sets of our receivers.
Because we are a run first team, most defenses are going to be playing some combination of single safety/single high safety defense against us. Contrary to what many people will often talk about, this is not where your burners are most effective, burners are most effective against 2 high safety coverage, because it forces a safety to vacate a deep half or quarter zone, opening up the middle/post areas of the field while also having the possibility of hitting the deep strike if the safety is out of position.
Here's some examples:
Here you'll see the Jaguars have come out in a cover 3 zone, press coverage. The press is really only from position, not necessarily meaning they will physically press the receivers. Our receivers do get free releases on this play. The yellow highlights the optimal routes to be a deep 3rd coverage technique because the corner will be looking to stay upfield of the receiver to not let the receiver behind him. This is the proverbial "island" so often talked about. That the corner has a tough job because the receiver has so many ways to go that the corners job is much more difficult. The red is the route Williams runs.
The corner gets into the hip pocket and uses his length to keep in position against the receiver(look familiar?)
Kaep is forced to make a back shoulder throw and the ball is incomplete.
Here we see the same defense again. This time Boldin is lined up against the same corner.
you see how Boldin determines how the corner is going to play him by running slightly towards the sideline on his routes to begin with which causes the corner to turn his hips slightly out.
Then, because Boldin turned the corners hips out, he's able to take advantage of the player who's hips are now out of position to take an inside route and create seperation.
You see how much separation is created in a short route because of the good route running against a cover 3. If this were cover 2 man or zone - which is created when we go 3-4 receiver sets, the receiver doesn't have the advantage of the corner having to play deep responsibility. The corner can squat underneath and keep his hips square to the receiver to not allow in/out/curl cutting routes.
Because all of our receivers are primarily route runners and runners after the catch, we look to get them in open spaces against their defenders. I think as badly as many of us want to see our offense explode into the Broncos offense or the niners of old, I don't think it'll happen. What I do see, is the additions adding a lot of depth and diversity so that defenses have to gameplan more for different players and, with an effective, steady dose of quick, good route running playmakers, we can force more teams into a cover 2 and open up the box for our run game and for VD deep. I think if we go multiple receiver sets - we'll actually work against our strengths.
Now, against Seattle, I see us imploring more 3-4 receiver sets because they're Nickel corner is a downgrade over a LB for them plus, Chancellor is not good in deep space because he's pretty tight in the hips.