Critique this plan?

[Jeffrey Bouquet]

  It seems I've a brick wall [too many ports to use pkg effectively ] -- [ 3551 ] 
and too many need ' pkg lock ' in ' v11 ' for ino64 fixes, 12.0-CURRENT, and quite a few
others fail to build from ports, either compiler, so are also 'pkg lock ' or in a few
instances binaries/trees copied from other installs, so that my DESKTOP can continue
running a if it were 2003 Microsoft based, vs 2004 Freebsd January based, where a reinstall
seems in order OR, I should just sit and wait til 13.0-CURRENT and proceed that way.
..................
  Meantime, how is the following as a workaround
  mv /usr/src /src-2017
  mv /usr/obj /obj-2017
  mkdir -p /usr/src
  mkdir -p /usr/obj
  cd /usr/src
  bw, etc
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or
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 [ clean install ]
 mount -t ufs /dev/gpt/2004root /mnt-root
 mount -t ufs /dev/gpt/2004var  /mnt-var
 mount -t ufs /dev/gpt/2004tmp  /mnt-tmp
  mount -t ufs /dev/gpt/2004usr /mnt-usr
 into which I surmise an installworld would fail as multiple DESTDIRS are included. 
.................
  nullfs ?
...............
 Revert to all-in-one / system, no /var /tmp /usr?
.............
 or some new install 
.............
  None of these are plans as of yet, save proceeding without any upgrade whatsoever.  I recall
unpacking base.txz [etc] to fix a failing installworld in the recent past, so any foolproof
method of that would also be welcome.  But I suspect much would remain undone, 
initial *proper* setup of /etc/mail, /etc/groups, as well as the loss of fine-tunings I've
done over the past 13 years or so, if it were done preplanned as a new-then-rsync-the-old
system-over-it sort of reinstall  [ not looking forward to undoing years of week-by-week
this-rc  that-rc fixups...      newbie in so many areas who just copy-pasted the
work of others into this system, to excellent, usually effect.    ] 
.............. 
  Apologies for the email that went on three times longer [ more verbose  ] than I planned, sort
of making its Subject:            a  misstatement of the body of the email.
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