Wikimedia Bugzilla is closed!

Currently, with numbered and unnumbered lists, you can have sublists, but you cannot easily "go back to the previous level" after a sublist.
- You can start a new list item.
- You can use an indent : to continue your previous level
  after the sublist, but (depending on installation, skin,
  and local CSS) that does not always render as intended.
- you can put a <br /> plus a <span> or <div> with some
  arbitary intentation at the end of your last sublist item.
  Besides being a structural sin, that hardly renders
  as intended with many skins, and browsers.
- You can wrap your sublist in a <div> container, but you
  usually need to know many peculiaritites of CSS and
  browser oddities in order to make it really work.

I want the latter be taken care of with a simple wikitext
syntax, basically signalling:
 1 - "continue with, or return to a previous level" or else 
 2 - "omit list tag, and do not increment count"
whatever the implementor chooses.

I clearly favorize solution 1 since it preserves structure,
thus giving more logical xhtml.

Since having "-" (minus, standard dash) immediately behind
a wikitext list designator or indentation mark (*#:;)
is fairly uncommon, I suggest extending wikitext syntax by
these:
*-        back to the * level, continue with previous item
#-        back to the level of the # 
:-        back to the level of the :
;-        back to the level of the ; (start with new label)
All of them terminate sublists/indentation up to the level
of the *#:; preceeding the - and continue the last block or
item on that level without starting a new list item or block.

Sample:
# Here starts number one, having:
#* a subitem
#* another subitem
#** with a sub-subitem
#- and a continuation on the #1 level behind all subitems.
# Here starts nuber two, now.

If a list item or block is to begin with a minus sign or dash,
this syntax must be used:
* -       unordered list item beginning with a dash or minus
# -same-  ordered list item beginning with a dash or minus
: -16 km  indented block beginning with a minus sign
; -       start of definition list label with minus or dash

If - is not seen as a good choice, I suggest _ (underscore)
as another possible candidate. Also . (dot) might be worth
considering.