2D Background texture flickering

Hi! I'm developing a 2D graphic adventure in Unity with multiplatform support and I'm a bit lost with resolutions and textures. Currently I did some code to split the backgrounds (big and high resolution) in squared POT textures, place them in planes and I set the texture options like I read in the forums (although the result is better with Bilinear on instead of point).

The planes fit well together, but as we are targetting different resolutions (from phones to PC/MAC) the texture sampling produces artifacts (I think is called flickering, am I right?) when using smaller resolution than the texture size (tested point, bilinear and trilinear). If I understood well, pixel perfect matches a specific resolution, so I cannot do it that way as I would have to have too many texture versions.

Can anyone give me some hint about it? The visuals are very important in this game and the artifacts are disturbing. My thoughts are:

• Use different texture sets for different devices (512, 1024 and 2048), tested and not bad altough not perfect. Some flickering remains at some resolutions, and 512 doesn't give enough quality at some resolutions too (externally resized in Photoshop).

• Use dynamic texture scaling in code to fit the resolution, probably resource hungry (maybe the could be cached?)

• Use a custom shader so it handles better the sampling? (maybe mixed with the first option to speed up)

Thanks in advance :)