I've been playing colorless version for the past 3 leagues going 4-1, 5-0 and 4-1. The first 4-1 should have been 5-0 most likely as I made a big mistake against RUG delver losing my Mishra to Nimble Mongoose.
League mono 4-1
BUG delver 2-0
Food Chain Wasteland MVP to slow down
RUG delver 1-2
Shardless 2-1 All is dust MVP
Food Chain 2-1
League mono 5-0
Miracles 2-0
UWRG Delver 2-1
Mirror 2-0
Epic Storm 2-1
Burn 2-0
League mono 4-1
RUG 2-1
Elves 0-2
Painter 2-1
Burn 2-1
UWB Reanimator 2-0
4 Endless One
4 Matter Reshaper
4 Eldrazi Mimic
4 Reality Smasher
4 Thought-Knot Seer
2 Phyrexian Metamorph
2 Simian Spirit Guide
4 Chalice of the Void
2 Dismember
2 Umezawa's Jitte
2 Warping Wail
2 Thorn of Amethyst
4 Ancient Tomb
4 Cavern of Souls
4 Eldrazi Temple
3 Eye of Ugin
3 City of Traitors
3 Wasteland
3 Mishra’s Factory
4 Leyline of the Void
2 Warping Wail
2 Endbringer
3 All Is Dust
2 Pithing Needle
2 Ratchet Bomb
I've been actually very happy with the Thorns again (and feel like 2 is a good number, surely not 4) as they have surely slowed down opponents library manipulation. Wasteland I have liked as well, it has helped to slow down opponents as well. Earlier I might have been too aggressive with the Wasteland losing my own aggressiveness by not deploying more threats first so it might be that my skills haven't been where they should be. Occasionally Wasteland + Thorn is obviously very good. Also I have not missed Urborg.
Phyrexian Metamorph has been only ok so that is definitely flexible slot depending on meta and as a prove to my inexperience with the interactions I though Metamorph could copy a creature that is put into play by Show&Tell :P Will try something else there next time.
About sideboard:
All Is Dust has still been great. Ratchet Bomb has been borderline as for the token match ups I have had my chalice on board as well so using it for zero is not the best thing you can do but sometimes have to do. I think colorless still needs Ratchet as a catch all answer to lots of stuff like Ensnaring Bridge as discussed before. Leylines are very good where they need to be.
With this list I most likely sideboard as follows, at least in general (hopefully I can get some advise here). The order of the match ups and the deck lists we are supposedly facing is based on
http://www.mtggoldfish.com/metagame/legacy#online I've left this intentionally without my reasoning for each choice to get some objective advise first.
Miracles:
- 2 jitte, -2 metamorph, -4 reshaper
+2 ratchet, +2 wail, +2 all is dust, +2 endbringer
Mirror:
- 4 chalice, -2 thorn
+2 Endbringer, +2 ratchet, +2 needle
Shardless:
On the play
-4 cotv, -2 metamorph
+3 all is dust, +1 warping wail, +2 endbringer
On the draw
-4 cotv, -2 metamorph, -1 endless one
+3 all is dust, +2 warping wail, +2 endbringer
4c Delver:
-4 mimic, -2 metamorph, -2 dismember, -1 endless one
+2 endbringer, +2 wail, +2 needle, +3 all is dust
Burn:
-2 dismember, -2 metamorph
+2 ratchet bomb, +2 warping wail
Deathblade:
-4 cotv, -2 dismember, -2 reshaper
+3 all is dust, +2 endbringer, +2 needle, +1 wail
ANT:
-2 jitte, -4 reshaper, -2 dismember
+4 leyline, +2 ratchet, +2 wail
Reanimator:
-2 jitte, -4 reshaper, -2 endless one
+4 leyline, +2 wail, +2 endbringer
Death&Taxes:
On the play
-2 thorn, -2 wail, -1 mimic
+3 all is dust, +2 endbringer
On the draw
- 4 cotv, -2 thorn, -2 wail
+3 all is dust, +2 needle, +3 endbringer
Lands:
-2 jitte, -2 dismember, -4 reshaper
+4 leyline, +2 needle, +2 endbringer
Sneak&Show:
-2 jitte, -2 dismember, -2 reshaper
+2 wail, +2 endbringer, +2 needle
BUG Delver:
On the play
-2 metamorph, -1 endless one
+3 all is dust
On the draw
-4 cotv, -2 metamorph, -3 mimic
+3 all is dust, +2 warping wail, +2 endbringer, +2 needle
Hopefully this gets sideboarding discussion going :)