As an avid cyclist for many years, I put in much milage in the Texas countryside.
I carried (can no longer ride - shoulder problems) my G19 in a leather/zippered pouch on my gun belt, with a fully loaded spare magazine, a fixed blade knife, and a cannister of Freeze Plus P pepper spray as out in the country as there are lots and lots of free roaming attacking dogs. Oh, I also carried Sudecon Decontamination Wipes in case I got wind blowback from spraying an attacking dog.
Your gear carrying idea sounds more efficient than how I carried my self defense gear.
Never used the Alien Gear, but I have used the Concealment Solutions chest holster for a variety of different applications including biking, dirt bikes, hiking, etc and love it. They use their Cobra holster in the Chest Holster Combo so you could actually use it as an OWB or the chest holster.
We are a manufacturer of high quality custom holsters. We have designed a conceal carry holster that is not only functional but also comfortable to wear all day.