River raise??

[wesrman]

Both opponents are pretty much unknown.
Im new to short handed so i have very few hands on people.
Im wondering about the river.
Any reason to raise here or is calling correct with somone behind me (although he has allready checked)???
Also, does it change if there is no one to act after me???
Thanks...
$0.02/$0.05 No Limit Holdem
6 players
Converted at weaktight.com

Stacks:
UTG ($5.65)
UTG+1 ($5.43)
Hero ($5.39)
BTN ($4.53)
SB ($1.15)
BB ($10.66)

Pre-flop: ($0.07, 6 players) Hero is CO
UTG calls $0.05, 1 fold, Hero calls $0.05, BTN calls $0.05, 1 fold, BB checks

Flop: ($0.22, 4 players)
BB checks, UTG checks, Hero checks, BTN checks

Turn: ($0.22, 4 players)
BB checks, UTG checks, Hero checks, BTN checks

River: ($0.22, 4 players)
BB checks, UTG bets $0.2, Hero calls $0.2, 1 fold, BB calls $0.2

[Results Hidden]

[UG]

raise preflop, maybe not at this level though so limping isn't bad

raise river all day everyday

[dev]

I like a preflop raise to isolate the limper.

I don't know what weaker hands pay off a raise on the river, so yeah, I like a call here. The hands that payoff that we beat are 33(?!), and KJ. The ones that beat us are JJ, QT, and a flush, which I didn't consider much of UTGs range until I considered the alternatives. He could also have air, but air doesn't pay us off.

[wesrman]

I like a preflop raise to isolate the limper.

Usually i do, but i like to limp behind once in a while.
I should probably only limp behind if theres more than one limper i suppose???