I wouldn't combine.

I would decide on one or the other, add in some kit bashing/freelancing and patchout out the rolling stock and locos to match the location. Then get to work!

"I am trying to figure out

  I'd make it easier on myself and just pick one area of the country to model. It's a lot easier to make convincing scenery of one location  than have to switch to another type of scenery a short distance away. Since it's freelance why couldn't the Aberdeen branch have a quarry in Washington? or why couldn't the Aberdeen branch be located in eastern Pa?  I like quarry scenes on layouts. The SP had a sand quarry in the hills above town here and the sand trains were a highlight of the day as they rolled thru my neighborhood  .......DaveB

I was thinking...

Was thinking about just relocating the branch over to PA. I was thinking about all the other railroad conglomerates out there and I think that may be a viable option. 

I really like the locomotives Haines and Kibble House has and it is something of local interest to me. The part I just can get over is I dont think I would have the variety of operations like I do on the freelance I have right now.

As of now I have the following:

1. Transload facility that gets a wide variety of cars.
2. Rock unloading area
3. Food Processing Plant/Bakery
4. Steel/Metal fabrication facility
5. Cement/ready mix plant.

As for the other railroad I was thinking. It has the rock quarry but maybe i could incorporate some other aggregate as well. The line also had a feed mill on it, but that is serviced by NS. Was thinking about doing that, but having my freelance railroad service that. 

Another thought I had was having the rock unloading facility have a dedicated locomotive and that would pick up the cars that would be dropped off and drop them off into the rock unloading area. (Another thought)

Im just in the process of brainstorming. I dont have any ballast or scenery done on the lay out right now and the structures arent painted. Just wanted to gather some opinions before pulling the trigger.

Birdsboro

I model the W&N.

The easy way would be to back date the model or just pretend the industries are still open.

Birdsboro had a steel mill, a foundry, a feed mill, freight house, team track, interchange, and a manufacturing plant.  It could conceivably use several types of gons and flats, boxcars, covered hoppers and several types of open top hoppers.

Dedicated locomotives (plural) to handle the rock.  Its a 1% grade up to the quarry.  Several years ago when I visited the area, the quarry engines had Thomas the Tank Engine eyes painted on the north end of the back to back consist. Here is one of the engines headed up to the quarry with a string of empties.

This is the NS interchange yard, it used to be the yard at Birdsboro.  Its looking North towards Reading.  I am standing about where the PRR diamond was.  The PRR ran parallel to the yard on the left side (about where the road on the left is now and crossed here, going towards the right (the station and freight house are still there).  The RDG wye leg towards the Schuylkill River bridge to the right broke off about her and curved past that tree about dead center.  Hiding in the trees to the extreme right is the manufacturing plant, at one time it was the Diamond Drill Company.  Across the river and next to the main track was the Brooke Iron Works, which had a blast furnace.

Here is the FM Brown feed mill.  They also have a mill in Fleetwood, PA (where the original carriage works for Cadillac Fleetwoods were made.  In the foreground was where the W&N passenger station was and across the tracks was the W&N freight house.

Here is the empty train going up to the quarry on the Hay Creek bridge.  It was a mix of various types of hoppers of different styles and reporting marks.

Brown's

When I saw Birdsboro it reminded me of a time when I delivered wheat midds to Brown's on a regular basis, and would sometimes see H&K in action (smiley face loco and all). Thanks for the photo Dave, nice trip down memory lane. I often thought of the area as having good modeling opportunities.

I would second the advice about trying to stick to one area. I've done the "little of this, little of that" thing and it never came out well. It's hard in this hobby to limit yourself, I've been all over the map era and geography wise in my modeling, and have paid the price for buying too much, feeling flaky, etc. I have a lot of admiration for the modelers that stick to one road, one time period. That's my current goal. Best of luck in your planning.

More than one Washington

You could base your railroad out of Washington, Pennsylvania.  Southwest PA, not southeast, so the scenery is more hilly.  

The industries you listed are found all over the country, so that shouldn't stop you.  

Scott Chatfield

crossing gate

Not to be a rivet counter or anything, but isn't the railroad crossing gate supposed to be down when the train is going through the intersection?

(with respect to the first of dave1905's pictures)

It's invisible

What gate?

Scott Chatfield

Hrm

Hrm, there's some kind of a post just to the left of the cross buck, and then something extending up in the air from that, which is apparently a dead tree behind the house, it looked like a gate to me, with my blurry vision and the picture not enlarged.

That's why I don't try to count rivets. Can't see 'em anyway.

Article

Here is an article from the June 1953 Reading Railroad Magazine on Dyer Quarries, Birdsboro: