Your "current footprint can handle 1 xtra armory
(both lvl4) and TheHive set.
Now as per your suggested layout , hmmmm
551/439/464 ... T1/T2/T3 is your reg output, keeping production times the same, not counting your Boost%, according to aArchitect, and not taking into account game "value" of those goods (2.25-1.5-1) The game seems to ask for amounts "graduated" like 360 T1 - 280 T2 - 180 T3 in the Spire ( litterally, my current cost in my smallest city Lvl 2, enc 1, try 1 in the Spire (+coins/tools)).... and roughly those same ratios in your reg encounters, therefore your production should mimmick that 6 : 4.5 : 3, so even if you make all 3 types.... you'd make too few T1, and too much T3. I've never made T3, not in reg production ( bldgs huge ), I've always traded for it.... especially since globally there's already too much T3 floating around.
I have no clue if thats ( sample city ) "enough" to sustain all you want to do, but thats a different Q totally. SoggyShorts taught me to stay "balanced", so I used the game's examples of what it ask's for (ratios) , to balance out my cities. Once you have "more" , you can look @ not how many bldgs, but in a 24 hr period, what is your total output. Thats how I balanced things closer to that 6 : 4.5 : 3
per day. (even 5,4,3 works)
I want to have some extra low-level workshops and basic goods factories for events and FAs.
You Layout ( to me ) kinda fails there. Looking @ the tasks you saw during this event..... 9hour ( T1 ), 3hour ( T1 ), 5min, 15min, 1hr, 3hr, and 9hr (tools) ...... the stoppers really are the 9hr ones. Unless you plan to have a crapload so you can do all of those simultaniously ( you plan doesn't, mine don't either ), you're basically looking @ (5-6) T1 lvl4, and (4) lvl1 workshops xtra, with a minimum of (4) more workshops and (6-8) bigger T1. That alows you to keep (6) 9hr T1, or (4) 9hr groceries cooking, while still making other stuff and not impacting your reg tools/goods productions. Also the lvl4 T1 will upgrade fast ( not get bigger (planks)) for those tasks asking for 1-2 bldgs to lvl5 or higher. Then just rebuild back to lvl4, i.e.- rinse/repeat. You can cheat and just have (2) lvl4 and (4) lvl1 of the T1, just so you have 2 rdy to go, to upgrade for those tasks. When using just for FAs, xtra workshops all should be lvl1 ( for 2min brews ) and the T1 just needs to stay 2x1s (smallest) but could be lvl 5 ( for planks ).
You only need 2 "big boys" (workshops) cause if you sparkle them (PoP) you can recoup tools fairly fast, the rest can be baby ones. Lets face it, you can only time boost 1 at a time, so ya really only need 1, but not time boosting, 2 can fair well especially if they're Magic ones, or the biggest you can make naturally. I have (4) CH6 cities, and they all currently only have 7 total workshops each. I personally think its a "luxury" to have 4 xtra baby workshops and 6 baby T1, for those 9hr productions. They aren't need'd for basic functioning of my cities, just there for tasks.
You will never survive with just (1) lvl8 armory, especially without other bldgs producing troops. Plus, using auto-fight, will chew up troops faster than trying to fight manually..... So there, I shall just wish you "good luck w/that" if you try. Now, you will need "training grounds" so you can train 2 types simultaniously..... like Cerebus and Treant/Paladin, and
you can actually get by pretty well just using those 2 types. (95% time)
I do think once you get into CH5, 4x4 won't be enough ( and thats from someone who has run the tiny'est cities ) but if you have plann'd to use a 4x4 layout, I say add that land sooner rather than later, and get TheHive producing Frags now. Try to use any land you have, even if its stuff easily torn down/cheap, for other stuff. Open tiles are wasted tiles, even if you have some open flex space, to make moving stuff around easier, you can plop down a bunch of the 1x1 signposts untill you need to move stuff around, then just sell some off for the space.
Last off, remember .... your FS members/your neighbors can only "help", and you can only sparkle(EE) bldgs 2x2 or bigger...... So if you run a city that depends on help ( culture deficient ( <170% )) you need to have things for ppl to help. Good rule of thumb, is @least 2 of the biggest/best culture you can get, so you can keep those "sparkled" if need be (EE)..... My smallest cities have (3) ...... (2) 3x4s + (1) 3x3 , and they are the best "culture per tile" bldgs for thier size, ..... and for ANY size , Lava Codex 2x2 is the GoldStandard. They are always Culture only bldgs. Thats why sometimes its better to add a residence and a culture only bldg, rather than a culture/population combo bldg. For now I agree with your 2 Cozy Farms, but if you "win/get" a couple Magic residences, its hard not to make the case add'n those and cul only bldgs, rather than most hybrid bldgs. #1 rule tho, its not about what I or anyone say, its what works best in your city..... there is no right/wrong , just what works best for you.
Congrats on getting 5/6 of TheHive Set