I wish they would dedicate more time to improving cl.exe and link.exe in terms of performance and language support and less time with these hokey team visualization gimics. Every release since 2008 has been getting slower and slower for C++, the C compiler is awful, PGO instrumentation in Win8 is less capable, and there's no equivalents in the Windows ecosystem to gcc's likely/unlikely, oprofile, or valgrind. It's at…
It is never an either-or. It is always a complex mix of what customers ask for, what the strategic priorities/market realities are.
Often the problem with these queries is that there are not enough devs complaining to MSFT. No PM/engg manager is going to ignore a bug/problem if it shows up high in customer requests.
On promotions - I think it's the reverse problem. People only get promoted for working on something that's perceived to be hard.