1 tier vs 2 tier vs 3 tier

What are the pros and cons to a 1 tier, 2 tier, and 3 tier structure?

I'm moving to all-grain brewing after doing some partial grain brewing and taking a hiatus for a few years. I have my 10 gallon rubbermaid cooler and have started to convert it for my mash tun and am planning to get my turkey fryer this weekend. I'll also probably get a 10 gallon cooler as an HLT in the next few weeks and probably a single pump shortly thereafter.

I'd like to start building my structure now with the final setup consisting of 2 coolers, a single burner/kettle and a single pump. I can envision using a three tier gravity setup with the pump just going from the kettle to the HLT on top or a one or two tier system with some quick disconnects to allow moving the water/wort around with the pump. What are people's experiences? What are the advantages and disadvantages to these various configurations considering my proposed brewery setup?

As I mentioned, I'm new to all-grain and would like to take advantage of all the great expertise available here!

thanks,
kman

I am a single tier brewer with keggles. If I was going to use plastic coolers I would go all electric and all plastic like https://www.homebrewtalk.com/f11/bling-bling-electric-herms-conversion-93217/

Three tier has lifting issues for bad backs (me). Gravity means you can do without pumps.
Two tier is not as bad with the lifting.
Single tier and burner may not work with plastic cooler being too close. Make sure you give yourself room away from burner.

I have no actual experience with any brew rig, however, I love the set up linked above. The single tier all electric cooler HERMS set up is just downright sweet.

If I had the time, space, or money, thats the rig I would mimic...