I am in a similar situation, hoping to get into signals next year for my small HO layout. When I was looking into it last year, I found I liked the Atlas 3-LED G-style signals so when I get serious I will look at them again. I want them to change when trains go by and considered a system (I'd have to look it up) that senses with IR or optical sensors in the track, and turns from green to red, then yellow, but not totally prototypical. What method you use to change the signals will interact with the signal needs; e.g., if LEDs the resistor values depend on whether the signal system outputs 5 or 12v.
I'm not familiar with the placement specifics and guessing will just add confusion.
This year I did add some (NJI) switch signals for fun, placing one at each mainline turnout. Hooked to the Tortoise contacts, a glance confirms whether straight (green) or divergent (red). It supplements bi-color LEDs on my control panel. They may not be prototypical (only facing one direction) but I like the added feature. You might consider including some of these. They are made in silver and black.
http://www.modeltrainstuff.com/N-J-International-HO-Silver-Switch-Indicator-p/nji-1300.htm
Paul
Modeling HO with a transition era UP bent
I have been modeling for a long time and have a vast collection of HO engines, rolling stock, passenger cars, vehicles, and some buildings. My current layout is an around the room double main line with a branch junction at the passenger station. It is about 17' x 12' not includeing the staging yard which is where the branch line goes to.
I would like to start modeling signals. I am looking at both BLMA and NJInternational brands, I don't care about specific type as it applies to authenticity of the railroad. I want something modern for the mainline and older for the branch line. I might even have just one single search light protecting the junction for the branch.
How do I get started? I would like the signals to have some purpose, but not to detailed that I spend all the time worried about signals being correct and not operating trains. Can signals be on a curve? I have 27" and 32" radius curves which take of up a lot of space. If on the curve, are they on the inside and facing a little inwards so the train crew can see them from a distance?
I model GTW and BN, with some other roads for run through power. Any help is appreciated, thanks and Merry Christmas.