All people in this forum, both developers and testers, deserve the absolute recognition of the effort they make to maintain the functionality of Unity Interface.
Taking into account the announced prolonged 10-year support for the 18.04 version I consider priority an attempt to “polish” all small imperfections that are still present.
Most of the crucial functionality has been kept, but little imperfections as previously mentioned Help system or say the inability to show username on the toppanel (although the option is turned on) are still present. All this are small things that somehow “ruin” out of the box experience in an attempt to preserve Unity interface as relevant and viable option for wider audience.
Parallel development and testing of future versions (19.04 and up) is definitely needed, but due to the limited resources I certainly think the priority should still be “the ironing” of 18.04 version.
No matter of bug tracker reports, it might be a good idea to make a list of all the minor shortcomings at one place, so that developers and future testers have an easier overview of all the possible glitches they need to test or try to correct.