1911 recoil springs are available from 10lb to 24lb. It's almost as bad on the gun to over-spring it as it is to under-spring it. Over-springing a 1911 will make it harder to pull the slide back. It will "return" batter the barrel link, frame, slide, and barrel. Additionally, the brass won't eject properly and you will need to install a heavier firing pin spring with any recoil spring over 18 lbs, else you may get a slam fire (not with Colt Series 80s). Under-springing will damage the same parts in different places, probably worse.
Brass ejection distance is a good guide. Assuming your extractor is tensioned properly, your brass should land 5~6 feet away. If brass barely clears the gun, you are asking for malfunctions, risk return battering, and are using a spring that is too stiff. If your brass flies beyond 6 feet, your spring is too light and you will get "recoil" battering.
A good general guideline is to use the spring designed for the load you intend to shoot. No one spring weight is good for all loads. I know a lot of shooters that never change their springs when they change loads. Not good! Here's a guideline for 45 ACPs:
10 lb - very light target loads, 185~200gr LSWC.
12 lb - light target loads, 200~220gr LSWC.
14 lb - medium target loads, 200~220gr LSWC.
16 lb - normal factory load, 230gr hardball
18 lb - +P factory load, 185~230gr jacketed bullets.
20 lb - heavy load.
22 lb Â– very heavy load, up to 260gr bullets.
24 lb Â– used with 10mm Auto only.
Based on your post, I would recommend an 18 lb spring for those 185gr loads, a 16 lb spring for hard ball, and a 14 lb for your target SWCs. Keep in mind, the above chart assumes you are using the proper powder charge weight.
As for the full length spring guides, they don't make a gun work much better nor do they enhance accuracy. Mostly they are just another way to spend money and make the gun harder to disassemble. I like to do a "press check" before holstering to make sure I have a round chambered. This is done by placing your left thumb inside the front of the trigger guard and your forefinger over the spring plug. Squeeze and the action opens far enough to see if a round is chambered. Can't do this with a full length spring guide. Shock buffers are just as worthless. I can't believe people pay a couple bucks for a little piece of rubber. Mostly, shock buffers don't allow the slide to move fully to the rear. This can cause extraction and feeding problems. Yes, they do help keep the spring guide from getting battered but they don't do a thing for the rest of the parts in the gun.
In conclusion, use the "right" recoil spring and you will prolong the life of your gun.