Should you skip your first IO???
I’m assuming a few things: You’ll age up with the Imperial Academy; and I’m comparing single scout, IO first supervising 6 on food then 7 on food until the 4min 55s mark vs single scout, no IO, 6 on food, then 7, then 8 all the way to 4min 55s where you’d have your first IO pop out the Imperial Academy in the 2nd scenario.
Other assumptions being made are a 0.66 avg food/s gather rate and 1 tax per 15s, no wheelbarrow. Lastly I’m NOT factoring in COLLECTING taxes bc ideally the taxes uncollected are not losted, although there are multiple scenarios that might develop by being able to cache more of your tax sooner And whether or NOT skipping IO would influence these scenarios…i digress.
Scenario 1:
Pull starting 6 vil straight toward berries and catch the nearest straggler tree on the way with 5 of those villagers for 50 wood, the 6th build a house on the way, start to build the mill but not finish it and finally kill your first sheep. The 5 straggler tree villagers will finish the mill, drop off the 50w then rally to dead sheep. BUT the IO would have spawn before the mill finished building so you SHOULD gain 10w extra. We’ll pretend all that took 20s such that everything can basically stay on the TC 20s intervals.
(note: taxes will be calculated separately .)
So first 20s you generate 60 wood (10 of that wood was created by the IO, keeping track of this) and now have 6vils + IO on food for another 20s before the next villager pops out the TC. IO + 6vils = 7.2 effective vils. This means by the time the 7th vil come out you’ll have generated 95.04 food (15.84 of that food was ‘created’ by the IO). Finally we’ll keep 7 vils + IO all the way up to 4min and 55s; (40s, 295s]. Quick maff gives us 7×1.2×0.66×255= 1413.72 food (whereby 235.62 of that food was created by the IO thru alchemy…). In conclusion to scenario 1 you have 60w and 1508.76 food with 261.46 of that resource created (basically you just created a whole sheep plus 11 resources in the time specified).
Scenario 2:
Scenario 2 starts like Scenario 1 exactly except the the IO is replaced by a villager. This means you do NOT get the extra 10 wood…(noted). Next your first food gathering window is only with 7 villagers for 20s, not 7.2… so you only get 92.4 food. BUT here is where tax generated kicks in; you’ll have 1 more tax than Scenario 1 for each drop off bc of this extra villager. Finally once the 8th villager pops out the TC we’ve arrived to the (40s, 295s] window again. Quick maff 8×255×0.66= 1346.4 food. And surplus tax generated via Scenario 2 compared to 1 is 275s/15s= 18~19 tax. In conclusion to Scenario 2 you have 50w 1346.4 food and 18ish tax surplus.
COMPARISON
Scenario 1 GENERATED 67.32 more food and 10 more wood than Scenario 2 and magically created a sheep plus 11 resources. This mystical sheep is not meaningless if you’ll end up short on sheep, so it must be considered. However Scenario 2 would have ages up 10+ seconds sooner than Scenario 1 AND would be at a plus 100 starting resources (50f 50g… the difference in cost between a villager and an IO). So TECHNICALLY Scenario 2 would be plus 22.68 net resources cached the moment before Scenario 2 invests in making an IO. THEN even after Scenario 2 invests the 150 resources to make its first IO, it’s NOT coming out of the TC! THIS means the way Scenario 2 gains return on its IO is inherently different from Scenario 1’s. Lastly after all IO have been fielded Scenario 2 in a vacuum will always be effectively 1.2 villagers ahead of Scenario 1??? So the simple question becomes “How long will it take 1.2 villagers to gain 77.32 resources and magically create a sheep plus 11 resources ‽‽” And don’t forget the surplus tax being created by that extra villager in Scenario2 
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On paper, following the scenarios laid out, I propose skipping IO gains you faster age up and sooner double tax window. THEN it perpetually puts you 1.2 villagers ahead of the alternative which in the long run will eclipse any early bonuses generation garnered by the alternative and always have more taxes!!