What can I use instead of kobolds, goblins & orcs?

[SnowleopardVK]

I'm surprised they've only been mentioned once, in passing, but Drow can be good opponents.

...Of course at 1st level you likely won't get an opportunity to use Drider against your PCs, which is a shame. Still, make recurring villains and they'll eventually be strong enough to take one on.

Another neat option is Leshys. They're tiny and cute, and they can make for devastating (to low-level PCs) ninjas with just a couple of class levels. Pair them with an evil low-level druid and some plant and animal allies and you've got yourself a low level BBEG and minions.

And I've recently done a whole low level adventure for some players using soulbound dolls as the villains, mooks, and allies (a NE doll villain, NG doll ally, and CN mooks.)

 

[Systole]

I'm currently using pugwampi gremlins. The thing that's great about them is that they're really annoying but not terribly dangerous by themselves, but their aura of unluck makes them great mooks when paired with a BBEG later on.

 

[Scott DeWar]

I am the guest DM of a table top game where the characters go underground. in this enviroment they will encounter a swim challenge, grindylows, oread and later a variety of creatures such as the myconid, mudmen, elemental based creatures (elemental template).

sometimes there will be the advanced template, class levels, and other templates in the monster compendium.

 

[Set]

I like the Vegepygmies idea.

Giant Ants, if tweaked to have hive-minds and sentient queens with spellcasting ability, can make for an unusual low-level threat.