Research does seem to carry over, but not production. Many people (including myself) have asked for this, and there seems to be no logical reason for it staying that way, just micromanagement hassle, but it seems it's a useless fight against Stardock religion - Galciv did not have production carry over either.

Sadly nono the little robot is right it seems a religion and the lack of answer of Stardock indicates this won't change, despite many requests from many players since many weeks. 

All of the Civilization games had tile management.  Fallen Enchantress has no tile management economics - there is no turn-by-turn action that the player can take to change the amount of production in a city.  (Edit: The exception to this is changing city enchantments - but that spends another resource, mana, to gain a tiny amount of production efficiency).

If you can't increase or decrease production turn-by-turn, there is no need to worry about production overrun.  In Civilization, the player would have a small incentive to change production to trade / food temporarily then change it back.  Fallen Enchantress does not have such an impetus, so from the city production management standpoint overrun is irrelevant.

The point about the gold is valid, as that will push the city to the next item in the production queue, speeding it up by a turn.  A simple fix here could be for rush-buying to merely "fill up" the production gauge, allowing the queued item to complete at the start of the subsequent turn.  However, this would remove the immediate benefit of the "instant completion."  This immediate-reward system is one of the primary needs for games to continue to be fun, running off a similar concept to the chime or ring or spin that a gambler gets when playing a slot machine.

Perhaps a scripted placeholder "building" could be placed into the queue after rush-buying.  This "temporary" rush-buy construction could be called [Completing Purchased Infrastructure] or [Finishing Hurried Unit] and would last until the end of the turn before disappearing.  The player would be able to move around the rest of the queue, but not this initial item.

I would prefer if production would carryover too, this would really ease up on the micromanagement needs.
I have a little perfectionist in my brain that nags me everytime I forget these perfectionist items, and find it rather annoying to "have to" check my cities each turn, it also would help to make smaller-easier troops worth "more" since you will lose less production compared to maxing out units (which I find too necessary in the current game).

So I agree, please make production carry-over, its always nice when it happens, but it feels like a loss when you don't have resource-carry over... Grrr

Sincerely
~ Kongdej

You're going to bring up a realism argument for Fallen Enchantress, really? I'll entertain it for a moment. If what you say is a good reasoning for the lost production, why does all of the production become lost on project completing? Everybody works to the bone until finished project then parties hard for a couple months? If what you're saying was a valid reason, production would fluctuate every season to account for differing amounts of people "on break" and the varying amounts of work you get out of them in the real world.

My reasoning is basically the same as Kongdej's. I dislike the micromanagement that comes with checking all of your cities every turn for rush buy opportunities. It slows the game pace and flow down for perfectionist strategy gamers, which are high in number. I would much rather focus my time on my armies, tactical battles, pioneers, building decisions, and diplomacy every turn. I don't need build queue micromanagement added to that list.

I agree with what has been said, adding resource carryover eliminates unfun micromanagement.

Or, alternatively, if the desginers don't want production to carryover, convert the excess production into gildar.

Or, second alternative, make production carryover for fortress but convert it to gildar in towns and to research in conclaves. The conversion rate would be the same as when the city is building research or gold (they are adding this feature to LH).

Thanks

Simple is beautiful - I would prefer vanilla carryover (like in Civ 4 & 5)

But don't hold your breath...