After playing several games of the beta now, and reading the forums a bit, I had a lot of ideas on some mechanics that felt a bit weak or unbalanced.  So sorry for the wall o' text, but thanks for the patience if you read it.  I'm trying to keep the mechanical changes to a minimum but focus mostly on balance.  That said, I'll immediately go to the biggest mechanical change.

--Cities.  Too generic right now, so give them the "Champion Treatment" from WOM to FE.  To me this has several parts:
    1) Dramatically increase guildar/ material upkeep of improvements - if you try to build everything you hobble yourself, but can still choose.
    2) The Champion Treatment : On city leveling, give a grid of perks and let the player choose 4 or 5 (you could make cities level a lot more - say to 20 or 25 with a single perk per level, but this would become annoying in large empires).  Some perks could be unique buildings, like now, but I'm thinking more reduced maintenance for building XYZ, or increased yield.  Level 2 inns,etc.  Perhaps free city enchants, civic laws that give bonuses.  Things that give traits you can build into units, etc.  Auras.  Like with Champions you'd unlock a "path" for a city early on (and a more generally OP one for capitals), and that determines what sorts of perks you get.  I'm thinking this sort of thing worked really well already for champions, and gives a way to specialize without a lot of mechanics, and it lets the player pick to use a non-efficent building if they want, but have to plan for it.
    3) Condense some of the +flat bonus / +% bonus buildings into earlier buildings, make the latter ones more unlock traits, or give general empire wide bonuses, etc.
    4) Make buildings take longer to construct.  Basically if you're making less, can take longer so they feel like bigger choices and emphisize building vs troops.


--Baseline Stats.  Things like Strength, Con, etc seem a bit bland when increasing. Towards the midgame it feels like dodge and such lose meaning as most troops/ champs can hit anything pretty easily.  Make the stats do more.
    -Basically I'd like to see high con units have a lot more HP, high dex a lot more dodgy, etc.  This could keep some of the early game interesting battles further into the game, and force more tatics in battles to deal with enemies (rooting/ debuffs having a bit more emphasis over just casting dps spells or making glass cannons with high intative).  I focus on Dex/ Con as Str is both damage and encumberance (equipment amounts) so that seems pretty strong already.
    -Perhaps add a bit to baseline HP of everything.  Again, mostly trying to avoid one shot kills (so not worrying about counter attacks) and a wider range of units feeling more powerful.  Again, forcing more tatical attention to debuffs than straight DPS.
    -This would also make having "good traits" feel better than just having tons of equipment on custom units, which seems needed.


--Champions.  I like them, but they get strong quickly.  Add more traits, but a bit less powerful.  Raise curve for XP need per level.
    -Here I'm thinking a lot more +1/ stat traits, or weak abilities.  Make those rares and uncommons feel special.  It would slow the power curve of Champions, making them less of the fast way to become a doom stack.  Also having more weak traits could keep players on a specific path longer, and have Champs be a bit more specialized, which also would be nice.
    -More of a curve for XP just to slow some of the 5-15 levels of champion growth.  Seems too exponential at the end, too shallow to start, leading to super powerful fast, then having to kill everything on the map to gain a single level.


--Equipment.  Special stuff a bit more rare.  Again just halping to smooth out where Champions become super powered and have more of a "wow" factor when you get something great.  Increase shop costs more (+30% or more?) especially for horses and magical items/ higher powered things.  This is offset by more of your base stuff being picked up in the world.


--Resources.  Right now feels like I don't have any, or I have an effectivelly infinate amount.  I've never had to delay building a unit for lack of a resource.  Introduce some caps (slight mechanic change).
    -Here I'm thinking an iron resource might give you say 5-10 units of metal, but it doesn't go over 10 per iron resource.  If you use some iron, it regenerates at +1 per turn until it gets back up to 10 units.  No infinately huge stockpiles anymore.  This would force the player to decide on bigger groups of troops, or better armed but smaller.  Or pick the types of armor / weapons a bit more carefully.  If you could plan your game to grab a ton of resource tiles, you get to have your super stack (which seems fair).
    -Also it would make diplomatic trades for resources interesting.


--Custom units/ non champion units.  A variety of changes here to make them a bit more interesting.
    1) Encumberance
      -UI: If encumberance is supposed to be the biggest balancer, first show tooltip on encumbrance, and make it more prominent when building.
      -Encumberance should matter more, perhaps more -accuracy if encumbered, or -dodge / -moves.  Perhaps add encumberance if you have a ton of special items (like telescope, compass, etc.  Right now since its purely weight focused, it has to take into account full plate for endgame, but that makes units you'd use most of the game feel like you can stack on everything.
      -As mentioned in baseline stats, having them matter more might make chosing strength traits / others effect encumberance issues more.
    2) Traits - a bit more interesting
      -These are mostly covered above.  If baseline stats mean more, adding them feels more powerful compared to just equipment.  If there's added traits for city leveling as mentioned above, some more interesting things could unlock (like throwing knives, or group blocking bonuses, roots, whatever).
      -Make traits a lot more expensive.  In upkeep as well as build time.  If I want to make a super unit, I should pay for it.  I still get to choose though.
    3) XP - Like champions adjust the leveling curve.  Reduce the benefits to leveling a bit HP and damage wise so that huge groups of units don't become super powered vs single huge units quite as much.


A lot of things.  But the basic idea is to have various aspects feel a bit more specialized, a bit more unique, but have to make some more choices along the way.  Combat being a bit longer, and less dps focused, a bit more on countering and debuffing.  Hopefully bringing Champions and units a bit more in line with one another power wise.  Making cities more unique, just like FE made champions feel much more unique.

So just my thoughts.  There are a lot of other ideas, but since some involved a lot of mechanical changes, so this is the less changy version of how to change things.  Hope it sparks some discussion or can help make the game even better.