Lighting scene - questions about time and noise

Hello community,
I work at a lighting company and sometimes create ‘renders’ or ‘impressions’ of how our lighting might fill a room - all of this is inaccurate of course, we use simulation software and photometric data from our lights to generate lux levels to make sure we meet safety requirements etc.
I use blender to create these ‘impressions’ to better show the layout or the style of the room, but I’m always having trouble getting rid of all the noise from cycles renders.
I’ll attach an example scene I’m working on now and break down the types of light in it.

The square ceiling panels are an emission material.
The circular ceiling lights are a dimmer emission material with a spotlight positioned in front to mimic the beam angle.
The lights shining on the walls are an area light at 42°.
The blue light on the perimeter of the ceiling is another emission material.
All other surfaces are default material (except in this scene for a procedural wood texture(not expensive)).

This render took 18 minutes at 1920 x 1080 with 500 samples, 1 bounce min / max. Nothing else is changed or optimised.
The machine it’s rendering on is a Core i7 4770K stock - Nvidia GTX770 - 16GB Ram - Windows 7 64bit / blender 2.71 64bit.
I guess my questions are :
Should these renders take this long? (GPU is maxing at 100% during render)
For interior scenes are these the right type of lights?
Is increasing the samples the only way to get rid of the noise?
I know 500 samples is not high, and the bounce is low, but at this resolution it’s taking nearly 20 minutes already, and I’m experimenting with limited success at editing multiple renders on different seeds in Photoshop after.

I’m probably asking a lot, but I’ve been working on these type of scenes for months and always try to find new ways - just nothing seems effective.
I’m also aware that I might just be impatient, but I can’t afford to leave my machine running renders for hours in the working day and these projects come and go quickly, for multiple scenes / angles there are not enough nights in the week to leave it running.

Thanks for any feedback!

did u try to add some clamp for direct and indirect light in render panel ?

but I think the bigger the emission plane are the more noise you get !
so need to increase the samples to compensate

another trick for fluo there is another way to do it let me come back for the trick

happy bl

it should not really be so noisy you got some set up that are wrong in the render panel
I did a false ceiling with some fluo
the fluo have a normal low poly map as Fresnel refractor
and a small bump voronoi map on the tiles
need to zoom in to see it

happy bl

there is the other tracer in cycles call Batch path tracing which is less noisy but may take a little more time
and a little more difficult to set up
check out the wiki for cycles for this tracer!

happy bl