It depends...
On a budget and for ease of use a acoustic combo works for me.The Ibby Troubador combo's are pretty good for the $. A 20w can get loud - though it won't hang with a drummer. A fishman loudbox is a step up and probably can hang with a calmer drummer (such a thing exist?)
Can always go for a powered wedge too - possibly better than a combo - laney do some reasonably priced wedges.
Don't get me wrong - I do like @JGP's solution, it'll get the most out of a existing pedalboard setup. And it is VERY giggable. You'd be able to DI the hotone and use the speaker as a monitor. Though if I'm already using a multifx, I'd not want to add another layer of amp sim's/eq - for me (now), simpler is better.
One thing I DO like about the multifx/powered speaker route is that the possibility opens up to easily add stereo to the rig...if I did a lot of textural stuff (ambient/delay/modulations), I'd think about that.
