Since most of the Forum regulars are at end-game (or at least have access to high * rated late-game Troops), I thought it may be worth passing on my own recent Spire Combat experience, because I myself have just (today) moved out of Fairies and into Orcs & Goblins. I have found that entering O&G has caused all of my Spire Enemy Troop Units - or at least those seen past Encounter 12, where I was when I started O&G - to be uprated from 2* to 3*. This makes a very large difference to my ability to use Combat in the Spire; speaking as an almost exclusively Manual fighter of somewhat above-average ability, I now find that where I was formerly able to fight about 75% of the Spire, I can now fight closer to 25%. I never Auto-fight in the Spire.
Therefore Goods and Resources will become a far greater Spire priority than formerly, at my stage of the game - and I would also suggest that the Mercenary Camp, certainly until its Units are at least at 2* and probably 3*, may well be almost completely useless (for both Spire and Tournament), and the Training Grounds, too, are of very questionable and niche use only, unless my presently 2* Cerberus Units (either through gaining 3* status or because the game's Combat system is considerably altered to better favour Melee Troops) become much more useful than they have been up until now in either the Spire (always) and/or the Tournament (since the new version). I find that the Spire Enemy Units are almost always best opposed solely with LR (75% or so), HR (20% or so) and Mages (5% or so), and since the new Tournaments began, the same is now true of those battles, too. NB: I play as an Elf, so it's worth mentioning that Human Priests may be far more useful (in terms of Mage use) than my 3* Sorceresses, and my 3* Golems may be better than Mortars, although more often than not, my Orc Strategists (5 x GotoS), even though only 1*, are better than Golems.
As far as Goods and Resources production goes, I can sustainably reach the end of Stage 2 of the Spire each week, and sometimes further (although it becomes extremely expensive, so I do this only rarely) with 6 x Tier 1 and 2 x Tier 2 Manufactories (currently fully levelled to end of Fairies), plus only 1 x Tier 3 (still only at level 12), since at my stage the new Tournaments (and the Spire since it began) are very heavy on T1, less so on T2, and notably light on T3, and this level of demand has also, so far, generally applied to Research, as well. It is also easy, at least at the moment, to up-trade T1 for the other two Tiers, since the new Tournaments seem to have caused a much increased T1 demand on my Server (Arendyll) and many Cities, especially larger ones, now very often down-trade, including T3 for T1, whereas Cross-Tier Trades (in Standard Goods, at least) were generally quite rare before the new Tournaments began to take effect. This will probably change in the long term, of course, as players adapt to the newly created T1 Goods demand, but even before the new Tournament, I did not find my Goods unbalanced (or my T1 in excess) while using the same T1:T2:T3 ratio (no need for Cross-Tier).
I have 6 x non-Magic Workshops, currently at one level below the Fairies maximum, and they are more than sufficient (without Endless Excavation or Prosperity Towers), although I do have three Evolving Buildings which provide about a further 2 x Workshops' worth of Supplies per 24 hours, which obviously helps a lot. Coins are no problem at all at my stage; I have far too many and have to waste them each day (based on Population coming almost exclusively from 3 x Magic and otherwise Standard Residences; I have few Pop/Culture hybrids, and my Culture bonus is 160% unboosted).
I have five AWs at present: Golden Abyss, Martial Monastery, Needles of the Tempest, Mountain Halls, and Dwarven Bulwark (which I may or may not replace with Shrine of the Shrewdy Shrooms; or I may keep both), and only three Armouries, levelled-up to the end of Fairies. I have only two Premium Expansions and do not intend to buy more, although my lack of space (I am also avoiding placing three Standard Expansions currently in Inventory) is something of a problem in terms of Population - hence the low number of Armouries and the low-levelled single Tier 3 Manufactory. I tend to stick with what appears to me to be an 'average build' (which is why I do not much rely on Pop/Culture hybrids), since I feel that this is probably what the game's devs expect and so I am not likely to encounter unpleasant surprises, as it were, in the future (e.g. nerfs which are difficult to incorporate into less 'standard' builds), but of course much of my City could be better optimised (e.g. more Pop/Culture hybrids rather than space-hungry Residences, for example) if I were to be less cautious - or if, like your friend, I did not intend to proceed past O&G in any case.
Sorry to waffle on as usual (lifelong habit...) and I hope that the above info may be somewhat useful to a person at roughly the same stage as myself.
Edit : For some reason I kept writing 'Dwarves' instead of 'Fairies'... sorry for any confusion. Doh.
