Shrugs could be added in at the end of the back/biceps day. The reason I didnt add them is deadlifts work the traps quite well in most cases, however if shrugs work for you then its a good idea to keep them
The problem with your shoulders was only doing lateral raises (I assume you mean side lateral raises) which are an isolation movement for the lateral deltoid. It is generally best to stick to compound exercises. Dumbell shoulder press and Military press heavily hit both the anterior and lateral heads of the deltoid, while bent-over rows in the back/biceps day hit the posterior deltoid.
Your chest exercise on its own was ok, however many people require two exercises for chest to see the best results. Flat chest exercises hit the Sternal head of the chest, inclines are to hit the clavicular head also. Basically you're hitting the whole of the chest, as opposed to one part of it.
Your tricep workout wasnt too bad, you had two good compounds. The only change I made here was adding only one compound after chest/shoulders as pressing movements heavily use the triceps. However, if you feel like you need a second compound movement it would be ok.
On the back day there are a variety of exercises to hit all areas of the back. Deadlifts primarily target the lower back and traps, bent-over rows hit the upper back and lats to a degree while chin ups are primarily a lat exercise. All of these back exercises work biceps pretty good aswell, hence the back/bicep combination. Generally one bicep exercise after working back will finish them off, but you could add hammer curls aswell should you feel they need working more.
On the leg day there are squats which hits the quads and stiff-legged deadlifts which target the hamstrings. Squats themselves also hit the abs so its a good idea to do you ab-crunches on this day. Also, although squats are usually enough to make the quads grow I personally dont find them enough. I usually follow squats with one more compound such as leg press or close-stance hack squats which are particularly good for hitting the vastus medialis (teardrop muscle). Basically the routine ensures you hit each body part once a week with high intensity and then it has 7 days to totally recover for the next workout.
Hope this helps