Ranger Freelancer is a solid choice. Multishot at... level 90, I think? Just attack move to as many areas as you can, defend empires (even if you're not getting paid by them, they're the ones that end the game more easily) and try to level up. Once you get Wood Nova you can start venturing a little into the bottom left and killing the occasional high level minion. I highly suggest Sword skill first; it gives a good balance of health and damage. After that, get Hand to Hand maxed for damage and finally Bow for a bit more damage/health and a little bit of range. Sell anything you find and save up for a decent weapon or crown.
Another decent combination is Necromancer/General. I'd have to look up skills for this one because I haven't played non-empire recently, but it generally involves getting the mana shield skill and letting your minions do all the work. Get at least one healer and one aura minion, the rest can be whatever you want (preferably ranged units).
As far as Empires go, I could write a relatively in-depth strategy guide, but here's the quick and dirty (as far as my method goes; pictures will be included later once I get to my computer):
1) Choose Resource as your empire type (outpacing other empires in technology > having some base unit advantage) and find a good spot. This should have a decent amount of room and be defensible, with a maximum of two entrances.
2) Build a Town Hall near trees, and Ungrow (a skill on your workers) any trees that you aren't using. Generally, you will want to build a couple Wood Houses around the trees you are using to maximize lumber efficiency. Once your Town Hall is complete, pump out peasants until you have about 20-25 food used up.
3) [picture will be used for clarity] Start building your housing area. Shift+Click=building in a queue, so you can have a relatively large area scheduled for building as you go and tend to something else. My general housing area is a grid that has a good amount of houses and allows for Fire Departments to easily access any burning buildings, as well as covering the entire space with population boosters. Once you have at least campfires, you can safely get your Commercial/Industry to a maximum total of 20 without significant population decay. It also allows for extra workers (and later, repair bots) to patrol constantly with Repair right clicked (so it autocasts) and repair anything that catches fire without you needing to worry about it. I usually use two for this.
4) Don't forget to build farms. A constant check you should be doing is on your food, and increasing the tax/food ratio as needed. I find that, depending on the circumstances, a 1 to 3 ratio works well, keeping everyone at maximum happiness, but results may vary. Also, don't forget to research at least two ages from the basic one; this will allow your houses to upgrade for a good population increase.
5) Build some rudimentary defenses at your base entrances. I never have to rely on a hero to defend for me anymore; you should build enough walls to cover everything up to two spaces, and gates for the remaining two (pics to clarify). A space behind this, build up three towers on either side of the gates, otherwise certain mobs will be able to reach over and kill your towers over your walls. You should never need more than one line of walls, as this makes it so that workers repairing it will get "stuck" trying to repair something they can't path to. Generally, one worker is good enough for each defense spot.
6) Constantly upgrade your age, and constantly build new farms. Depending on the version you play, you may run out of space for farms, so expansion may become a necessity. Because of the way I build (which creates less lag) you need a higher tax/food ratio to keep up with other empires that mass houses.
7) Somewhere around Imperial, break off 5 points for Science, and build a Foundation->Upgrade it to a Science Lab. Do at least one Housing, Grain, and Defense research, then start getting Lumber Harvesting upgrades. You may need to build a Barracks or two at this point to help out heroes with destroying obelisks/camps, but it's situational. Upgrade walls and gates before towers, and pump out peasants until you have about 50 food's worth of them (this is mostly to help lumber production, you can kill off some if you need it for military units)
Tech to Future
9) Research Airplanes (under the Tech Research tab)
10) Build ~36-48 Wraiths, about 3-4 control groups (and upgrade them; Weapons, Armor, Health and Movement researches at the Science Lab; Wraiths are my personal preference)
11) Win game by killing guy at bottom left