Millworkman, thank you very much for your help. Yes, I was speaking of moulded doors. I am also choosing door levers, and I like the Baldwin which is sturdy and looks nice. Would Baldwin levers look too heavy duty for my 30" interior door and one 26" closet door? I will use Schlage push button private levers for bathrooms. Any input or sharing of experience is greatly appreciated.

Flooring type seldom makes a difference with prehung units in the normal 82" to 83" rough opening. That height opening leaves plenty of room for setting the bottom of the frames to the necessary level for the flooring. Buying a slab is the best way to replace just a door. While hinge and latch locations are somewhat standardized, the specs are not universal. To locate the hinges/latch, lay the old door(with hardware removed) on top of the new slab. Mark the hinge and latch locations. There are latch installing kits sold at home improvement stores(about $30) that have the two hole saws needed to cut out for the latch. The hinge mortices are a bit different for DIYers. A template for hinges can cost from $30 to over $200 and a router is necessary to use those. A hammer and chisel is the old tried and true method, but chisels are generally not sharp enough even when new. I use several grits of sandpaper(up to 8,000 grit), a piece of marble slab(dead flat) and a $20 roller guide to sharpen chisels. (Called Scary Sharp.) Other sharpening systems run from $50 to over $500.

Assuming you are in Boston, there are many great "salvage" yards for older period homes in your area that would have period doors. Granted that will mean more maintenance and will not give you the "perfect" look that molded panels give, but imo, a home like yours would be ruined by plastic looking mdf doors unless you got creative with the painting process and purposely left the brush marks. Molded mdf paneled doors painted with a sprayer would be a major insult to your Victorian home, again in my opinion.

I am in a 50s house and wish my head had been on straight to select 3 panel. There were slabs when I moved in which created nothing in the way of decor personally and seemed drab or out of place. The panel doors I did choose brightened up the house and made everything feel clean/open. The only problem I had was with one opening requiring reworking the hinge placements on the frame. A first door was ordered with the frame and a total pain to install because of plaster walls, dealing with trim, angles, etc. I decided just to order the doors since the existing frames were smooth and sturdy. They fit easily into the frames and no adjustments needed. Suspect they were reframed at some point as I did not have any issues with angles or fit. You have a ton of options, the 50s tend to stay on standard sizing. With a blank slate as you mentioned, easy to go in the direction of your style. Although I wouldn't go towards too much design. A 3 panel would look great, which is where I wanted to go. A personal take as my one level cottage doesn't feel like it could take on arches. Even though it does have wall entries with arches. As for the exterior match, there are a number of threads which have mentioned this. The exterior of your home would be part of the deciding point. I have a front door sitting for install. It is a used solid wood door in perfect condition with a Speakeasy in it. 20s, Southwestern style? Still intrigued with it. I know the interior look will work, not sure about exterior. Far from the 50s, but these houses do give us some leash for decor inside and out. If you still have the original hardware, hang on to them. I changed all and now wish the solid aged brass was kept.