Right EQ for the kick
It’s not the best idea to boost the kick by using shelving EQ during professional mixing and mastering. Together with the bass drum boost, this equalization type will also lift a lot of sub low frequency bass part harmonics of the mix, which will only add blur to the overall sound. Use only bell EQ to enhance the kick on mastering. But first, make sure that there is enough space for it in the bass stem. If necessary, clear it with a sidechain technique and EQ, maybe it will be enough to process just this part in order to get a well audible kick.
Vocal to the foreground
Engineers often apply the following processing: they carefully lift the high mid frequency area with the mid/side EQ in the mid channel providing mastering services. This improves the vocal audibility in the mix. Depending on the vocalist’s voice tone, search in the 2-3 kHz area.
Quantity isn’t always quality
Be careful with the sound and don’t apply any processing without a well-considered plan simply because nowadays any studio is able to use a great number of top-level plugins. All these compressors/equalizers surely look great, but they are not the key for your mixing services success since they don’t make the sound ideal by themselves. It’s often enough to maintain a right balance and panorama, and the space of the song will become great without any additional effects. Besides, if the master bus of your DAW already contains a dozen of processors, but the song quality is still depressing, then you should take a step back and work with the mix in the first place. Remember that a quality sound of commercial tracks is achieved in several steps, each of which is equally important - you can check some it our mixing services examples. The principle “we’ll fix it later” isn’t going to work here.