Back in the day (1970's) I bought Bianchi holsters, and got almost every one lined. I have picked up some used ones over the years that were not lined. I decided that a lined holster was not a have to have option, especially with SS guns.
With your Blued 19, a lined holster might not be a bad addition. I would e-mail Ray and ask for his opinion.
The Inner Hammer Shield Option:
It is an extension of the holster on the body side that extends up to the approximate top of the hammer.
It has multiple functions.
When you wear your shirt tunked in with a cover garment like a jackshirt, windbreaker, etc it keeps the shirt from getting tucked in the holster along with the gun when reholstering.
It will do the same thing with your Tee Shirt with an untucked outer shirt.
Next it will help to keep oil and carbon off your shirt from contact with your handgun.
Last it will put a layer of leather between sweat and the gun protecting the gun a little better.
For $5 it is a good addition to your carry holster.
Enhanced Pancake vs Model 1 Pancake:
The Model 1 is a conventional Pancake with belt slots in the wings for your belt. Taking the holster off you take the belt out of the belt loops infront of the holster. Unthread it from the front holster slot, then pull the holster back and remove the belt from the belt loop behind the holster. Then slide the holster off the belt.
With the Enhanced Pancake you have Belt Tunnels. This holster does look sharp. When removing this holster I slide the holster back and forth as I pull the belt out of the belt loops and belt tunnels on the holster from the off side. After I worked this method out, getting the holster off the belt was not a big issue, just different than getting a belt slot holster off.
The Model 1 is handier if you are shooting a match with multiple revolvers, where you change holsters several times during the day.
Barrel Length: I have found that I can carry up to a 3" barrel revolver in the Lobo Pancake carried at 4 O'Clock and still get my billfold out of my right back pocket with no problem. When I carry my 4" 610 or 64 I have found that I need to carry my billfold in a different pocket. Another option would be carrying a 4" at 3 O'Clock, and going for your billfold by lifting your cover garment up at your billfold location, instead of sweeping your cover garment open in the case of a jackshirt.
I just made a run to town. I am carrying my Smith & Wesson 310 Night Guard in the Lobo Enhanced Pancake with a tucked in Tee Shirt, and an untucked Woolrich Elite 4 Pocket Discrete Carry shirt over it. I am carrying the 310 at 4 O'Clock strong side. I have 1 spare reload in a California Competition Moon Clip Carrier infront of the holster. For a light jacket I took along my Carhartt Jackshirt which has a nice long tail in Moss Green. Just in case I needed a jacket, which I did not.
I hope this information was of some help.
Bob