All the following suggestions/comments/opinions are the results of watching a druid in the party for 13 levels. I didn't play the druid personally, though, so these are outside observations.
1. A druid is a great utility character that can help in almost any situation. But the druid isn't the
best in any situation. Keep that in mind.
2. A druid in combat has two choices: spells or
wildshape. Take spells with range and utility, like
entangle (a
wonderful spell!) and
faerie fire, as well as heavy hitters such as
flamestrike and, at lower levels,
flaming sphere. When playing the spellcaster, remember to stay out of range. Your armor restrictions mean you'll most likely be vulnerable.
2a. Wildshape. Have a few animals statted and ready. Our druid chose one animal for each combat situation she thought her druid might wind up in. Remember that any spells cast on you before you change stay with you.
Magic Fang and
Greater Magic Fang are your friends. Our druid's favorite combat shape was a rhinoceros with a
Greater Magic Fanged horn. Later, dire animals pack a good punch.
3. In combat, you're better off
wildshaped, so focus your equipment purchases to bolster your spellcasting.
Pearls of Power are wonderful for druids, allowing them to memorize a single healing spell or buff spell or elemental defense spell, and cast it multiple times. At around fourth-level, the pearls become prohibitively expensive, but any decent druid should have at least a half-dozen 1st-level pearls, a few 2nds, and even a 3rd or two.
4. The one exception to #3 is a ranged weapon. Get yourself a good enchanted sling so that you can deliver missile fire when either your spells run out, or you need to stay out of melee range. Some creatures can make mincemeat out of even a
GMF'd rhino or dire bear, so caution is the better part of valor.
Our druid managed--through a random treasure roll!--to lay hands on a
+2 shocking burst sling. Since the damage die for a sling bullet is so low, adding elemental damage to such a weapon will give you the best bang for your buck.
5. You mentioned that your animal companions will be cats and dogs. This is bad from a powergaming standpoint, because those creatures, if taken into combat, will die very, very quickly. The best way to utilize the druid's companion (and the companion is a
large part of the druid's power,) is to invest as many HD as you possibly can in a single creature. The animal lives longer, becomes absolutely dreadful after spells such as
Animal Growth, and can be
Awakened once you get 5th-level spells, and start taking class levels. I'd suggest that your PC be caretaker to cats and dogs, but for his actual animal companion, he choose something stronger. If for RP reasons this simply isn't doable, then resign yourself to giving up a big chunk of the druid's power.
