Thank you for contributing to the forum and for your thoughtful suggestions! Groove templates are an interesting and useful suggestion indeed. I will forward this to the development team who works on firmware updates. No guarantees, but I will make sure they understand what you are suggesting.
Regarding your next question...you CAN change both the name and pad color of each of your 16 tracks!
1) First press TRACK
2) Select the Track you wish to edit by hitting any of the 16 pads
3) Now, hold SHIFT and tap the TRACK button to enter "Track Setting" menu
4) From here you can turn the dial and then push to select what aspect of the Track you wish to edit, for example Name, Pad Color, etc.
5) When done, hit BACK to exit
Next, I understand what you are asking for when it comes to seeing some visual feedback that indicates notes with long gate times, but the problem there is that there is no way to tell if 4 illuminates pads in a row is a single, long note...or 4 notes in succession.
We've addressed this by adding a TIE function. If you have a note on a pad (orange light) that is, for example, 1/16th note long...hold down the TIE button and tap purple notes after it to lengthen it. Try it out. The final purple tied note will have the gate time that you set for the original orange note. Now you can see how long a note lasts visually.
Lastly, regarding your last question: yes, that is called "Step Preview" and it is item 13-C in your global settings. I have mine turned off.