As far as starting civs, the Elohim are pretty vanilla with an emphasis on turtling which is nice if you just want to explore the various units and technologies. That and their world spell can save your butt when you get jumped by the Doviello or the Malakim (who are terribly upset about your choice of religion).
As far as general hints... hmmm.
- Build more warriors. Vanilla civ barbarians aren't much of a threat but the early game of FFH is much more hostile. Having at least two warriors per city means you can fair alright. If Orthus spawns nearby, spam another three or four so you can mob him if he comes your way.
- Research Education quickly. It gets you access to cottages, the Apprenticeship civic and the City-States civic. The former will get you free XP for your units and the latter will save your civ gobs of money once you have more than three or four cities. That one technology does wonders for your economy.
- Research Bronze Working early. If you get access to copper and have the Bronze Working technology then your melee units in a city will gain the bronze weapon promotion, increasing their strength by one. This makes a huge difference in the strength of your army, especially when you are fielding warriors and axemen. That and it allows your workers to chop forests.
- Get enchantment mana. The magic system takes some getting used to so pick something simple and play with it. That said, enchantment mana gives you one happy per city and allows you to buff your melee and archery units. Unlike other mana types (like entropy or chaos), the spells are pretty straight forward to grasp and the domestic benefits are very nice.
- When in doubt, pick the Combat promotions. FFH has a lengthy array of promotions available to various units but the tactical advantages of some can be hard to gauge. However, the bonus of the Combat promotions has been doubled (provides a 20% bonus instead of 10%) making them a good addition for any grunt unit. In other words, there is a lot to explore in FFH so trying to figure out the intrinsic differences between the civilizations AND the relative merits of each of the seven religions AND what the umpteen different spells do AND why your adept unit keeps gaining XP without actually fighting anything AND what the tactical advantage is to granting a unit cannibalism vs fear vs magic resistance vs scourge vs stigmata can be a bit overwhelming. So you can just slap combat promotions on everything and still be competitive while you toy with other game mechanics.
- Markets, elder councils and obelisks are your friends. All three are relatively cheap buildings and every one offers a small bonus that adds up nicely as you add more cities. If every city has a market then you don't really have to worry about maintanence costs until the late game. Obelisks get you the culture necessary to work your fat cross and quickly gets you a culture bonus to your defense that really helps you keep invaders at bay. Elder Councils offer a small science boost that can, if you turn a citizen into a scientist, becomes a substancial science boost. Again, if every one of your cities has these three buildings then the base necessities of your civilization (money, science and culture) will be met.
Beyond that, familiarize yourself with the other civs. Beware Hippus calvary. Clan Embers and Doviello make poor neighbors. Don't let the Sidar sit at peace too long or they will out tech you. Once the Sheaim get the Ashen Vale religion, expect the armageddon counter to start going WAY up. Malakim will invade you if you are a different religion and roughly the same strength. Ditto for Bannor. Don't bother trying to accumulate diplomatic bonuses with the Belseraph; they're crazy and act accordingly. Try not to be the first to invade the Ljosalfar. And so on.