Yeah w/ pollution I sort of just use mods that make look prettier... One great tip is to set your industry zone to farming, as that doesn't create any pollution. As to traffic problems, raise your highway up one level off the ground and run off/on ramps every 3-4 blocks along your main roads. This lets traffic that wants to take the highway (I.E. Anyone who wants to get anywhere) get there without greatly affecting the rest of the roads. OH another stupidly awesome method of solving traffic AND making good money is bus routes. If you make the highway the only way to get to your industrial zones from your housing, you can run bus lines all over city from your residential zones and reduce the number of cars on the road while at the same time, making ALL the moneys. My save currently reads €17,000+ on the cash bar. Oh. And read the "How to traffic" imgur album/guide if you haven't yet.