here is what I have so far
The idea is just to provide myself some terrain elements I can quickly drop in, complete with DC's.
Plains / Grasslands:
Tall Grass: This provides a %20 percent concealment to combatants not directly adjacent to you. It provides %100 concealment to opponents you try to use ranged combat against. You can also use it to hide.
Trees: Each tree provides cover if the tree is between you and your attacker.
Steep Hill: Forces a DC 0 Climb check to reach the top. It does not cause any falling damage if your forced back down.
Loose Earth Ravine: Climb DC 8 to reach the top. People on the top cannot attack those below with ranged attacks unless they are as far from the cliff face as the cliff face is tall, or unless the attacker is at the edge.
River: A wide river, at 20 to 60 feet accross. The initial 5 foot should be waist deep (Consider as difficult terrain). The rest requires a DC 10 Swim check. Swimmers get a cover bonus from attackers on land (+8 AC and +4 to Reflex Saves if at chest deep. Total cover otherwise). The attacker can ignore this with Freedom of Movement.
Shallow River: A very shallow river, that counts as difficult terrain costing 3 / 1 to cross. A DC 10 Balance check allows you to cross at 2 / 1. A DC 18 Balance check allows you to cross it at no extra cost. Crossing it while mounted requires a DC 15 ride check to convince the horse its a good plan.
Ditch: Just a 5 foot wide depression in the ground. It can provide Cover. A DC 10 Jump check to clear (DC 5 if running or charging).
Low Wall: A 4 foot high property wall. It is a DC 16 Jump (DC 32 if not if running) check to clear it entirely. If the player just wants to get over the wall, as part of movement, he can treat it as difficult terrain if he can succeed a DC 8 Jump check. If your not in a hurry, a DC 5 Climb check to climb over (but all you do is clear the wall). If you want to walk along the top of the wall, it is a DC 10 Balance check.
Mud: This is just difficult terrain, costing 2/1 to cross. But if a disarmed weapon lands in the mud, you will require a DC 15 search check to find it in the midst of battle.
END COMMUNICATION