Basically, resolution is how many dots per inch the printer prints.
There's a confusion out there, but the way it works out is that resolution in and of itself doesn't really have any bearing on print quality other than in being a major determinate in gamut size. And the reason is because in large format printing, there's always a smallest dot size. It's not like litho amplitude modulation halftoning where a five percent screen equals a five percent dot. In large format, even if a printer is a multi-dot printer, typically there's a smallest dot size, and it's frequency of that smallest dot that carries highlight and mid-tone detail.
So your prints will tend to be just as grainy -- or not -- at 360x360 as 1440x1440.
The real reason for higher resolutions in large format is to be able to use more ink. And the resolutions are simply stated as a measure of dots per square inch.
So, as I recall, I think the smallest drop size in your GS6000 is 6 picoliters. So if you're printing at 540x720, you can do this equation: 540x720 (the number of drops you're putting down in a square inch) = 388,800 x 6 (picoliters per dot) 2,332,800 (total ink volume per square inch.)
Then the question becomes: At that resolution, are you getting full gamut capability out of the printer.
And the answer to that question is in the profiling process.
Of course typically at that resolution you wouldn't get full gamut capability out of that printer a that resolution and at that size dot, and that's why the printer manufacturers have gone to multi-dot configurations. So then you'd have three dot sizes, with six pl being the smallest, and let's say 12 pl and 18 pl as drops two and three.
And that's the only purpose of multi-dot ink systems: To be able to achieve full gamut at lower resolutions.
Of course, that does come with a price. Fact is, inkjet printers love to print slow. The slower they print, the better they print. Only problem is that it's also true that the slower they print, the less money you make.
Many times, a given media will take a given amount of ink just fine as 6 picoliter dots laid down in 16 passes.
But try to lay down the same amount in 4 passes of 18 picoliter drops and the media will reject the ink.
This is typically seen as coalescence.
And that's the reason higher resolutions are available. You may be able to get the same basic gamut at 540x720 multi-dot as you can at 1440x1440 single dot, but it will likely not be as smooth a print, and might be fine as a banner, but not as a point of sale piece.
The way it breaks down is that all the things that have to do with how the RIP creates the actual printing dots are part of a profileable machine state. And that boils down to ink splits, dot sizes, ink densities and printing resolution. In order to change any of them, a new profile must be created.
Then you have the mechanical aspects of how the printer reproduces those dots. Typically those include number of passes -- the number of passes of the printhead over its printhead path to fill in that path completely with dots -- bi-directional or uni-directional, and printhead speed.
Those typically are not profileable.
As far as ICC profiles themselves go, what an ICC profile is in actuality is a characterization of a device reproducing color in a certain state. An ICC profile is made after all the variable machine-state settings have been set, and then becomes a part of the media profile for that machine printing in that state.
So no, changes to your ICC profiles are not going to help your issues.
Bottom line is there is a very lot to this. If you're really serious about getting answers, this is what I do for a living.
Please feel free to drop me a line.