@Jocular
It appears that map seed does affect gambling results. I am gambling boots and belts with clvl32 barb for back-of-the-napkin math about 100m gold. I gamble on one map until my inventory/stash is full, then reroll my map.
I acquire gold by clicking a corpse or Hollow Log near LK or UK waypoints. Currently I run in nightmare for max sell value of 25k gold. My current map seed generates mostly items that sell for 25k gold, with rare War Boots needing to be repaired and rare or superior Grand Crown selling for 25k without repairs. Note that in 1.00, repairing an item increases its sale value by more than the cost of repair, so repairing items is profitable.
A particular corpse or Hollow Log will *always* drop one of the same two items. In LK I roll until I get a map with Grand Crown/Winged Helm and in UK I will take a map that gives Grand Crown/War Boots. Rolling for this map can take several hours. To the best I can determine, the item fingerprint you get is determined by amount of time from entering the WP to clicking the object. That is to say, this method produces dupes, and taking the same path but waiting first will generate a different fingerprint. On my current map I most often get a Rare Grand Crown or a Rare War Boots and they always have same exact defense, durability, mods, sale value, name, etc. Sometimes I get superior instead, and it always has one of two sale values, and very rarely I will get a magic item that is always the same mods.
While running on one map, I notice groupings of affixes that appear on gambled rares seem to appear regularly. My current map seems to spawn boots with mf OR gf, two resists, life, often but not always fhr OR frw, and another affix that seems random/unpredictable. Previously I had a map seed that rare gambled boots spawned tri-res frw mf boots, but I never got a godly roll on it. On a different map I had boots that would spawn with str and dex giving me a few LLD potential boots.
When gambling, to increase my chance of failed uniques, I have put a unique belt and boot on my corpse and leave it dead. In situations where you might fight monsters this would be risky because of body popping, but since I never see monsters I can leave a corpse on the ground and not fear losing my equipped gear.
On my current map I gambled many mf/gf res res affix boots that I did not keep and did not screenshot due to low rolls.
I have kept so far two belts that both have Life lr GF + other mods
Boots:
GF __ Res Res fRw
__ Mf Res Res fRw Dex Stam
GF __ Res Res fHr Life Stam
GF __ Res Res fRw Life ED
__ Mf Res Res fRw Life ED
and a few boots that have similar but may not be part of the pattern
GF __ Res ___ fHr fRw ED heal stamina
GF __ Res Res ___ Life Str ED
GF Mf Res Res ___ Life ED
So it may just be that these are mods I like, and so I kept them and don't notice others, BUT I get these mods _a lot_ relative to other maps I have had. Also notice the prevalence of life vs other affixes (like str/dex). Also notice that almost all of these have two resistances, but I would also consider boots with one or three resistances.
My two tri-res frw mf life boots as well as one I did not keep were gambled on one seed.
So nothing definitive, but it certainly seems to me that affix patterns are strongly affected by seed. It is certainly true that on my current map I'm getting more boots of my desired affix pattern than previous maps, because I can *expect* a boot that makes me consider whether I should keep it every one million gold. Previous maps this just was not the case. My current seed has had no noticeable dry spells of running for hours and hours with no interesting boot, either.