skyteam - CO (nonsaver awards on all skyteam partners, and some other partners)
star alliance - SQ (nonsaver awards on SQ, including new F/J)
oneworld - AA (nonsaver awards on AA)

VS options >
~100K/night for ulusaba in africa
-2MM (earned by flying VS, so only works if you do) for space flight
-1MM for necker island celebration week (scheduled very few times a year, so probably doesnt work unfortunately)

you could also use up SPG by upgrading to specialty suites, at properties which allow you to do so. it sounds like you do plenty of business with them, so maybe theyd even let you combine plat status with a large amount of points to get a suite not normally available as an award.

EY also has nonsaver awards but im not sure how they work.