Well, I've not found adding 4 disc that useful for a large tank vs the venturi. So it's more born out of need than anything.
When you are not happy with it, you keep trying to tweak and torque things a bit. Same with the scape, or the plant growth or whatever.
You get better with time and the first few goes are not that great and pretty, but you know the general idea will work very well. I decided to switch back to sumps, bag filters, and venturi fed system instead of in line systems. I think the trade offs are not worth it for me.
Still, you need to go down and figure and think about each trade off and what is easier and better for you.
For me the sumps are great because:
1. I use venturi diffusion, I have no issues getting and dialing in any CO2 levels I desire and rapidly at that. If you have under powered systems that cannot respond nor as as efficient, then..........you might bad mouth the sumps/wet/drys etc. However, they are much better at degassing at night and keeping O2 higher during the day should you add too much CO2, adds another layer of buffering
2. I use about 1/2 the electrical pump energy wattage for the same flow
3. Plumbing is about 5X easier
4. Cleaning is easier
5. No water level changes in the tank
6. Easy to add other media and has a much larger volume than any canister made.
7. Can use any submersible heat, not just the Lifeguard and Hydor.
8. Better mechanical filtration using bag filters which do not infleucne flow rates
9. Less noise, actually about 1/2 or slightly less in the area of my house using a decibel meter(40 vs 20). This includes adding a hofner gruggle buster on the standpipe, but the external pumps are loud, use 2x the electric.
10. bad point is the built in over flow in the tank
Given those trade offs, the Venturi is far easier to add, as is any type of CO2 device in a sump.