I haven't used extract much (once), but that much caramel should make for decent body and head. Are you talking about a dextrin malt (like cara-pils), or a non-grain supplement? Part of it is the fact that that's just a small beer - it actually is kind of watery. 1/2 a pound of cara-pils would beef it up some. It's just like adding more caramel, but without affecting color or flavor much.

 

Yeah, just steep some cara-pills with the caramel. Actually, I guess it shouldn't matter, since the dextrin is the 'active ingredient' in the cara-pils (AKA dextrin malt). Be a matter for experimentation I guess. I know this is silly, but I've never used cara-pils because it feels like cheating. I'm only reluctantly concluding that I'm going to have to add something dark to my Altbier to get the color I want. Somehow I don't like to add something that doesn't have a taste/aroma function. I've got a batch of Altbier going that has cleared up well, it's got an awesome clean/malty/bitter/dryness like an Alt should, after a fairly proper lagering down to freezing, but the color is way too light. It's all Munich Malt (Weyerman Munich 2), so there is no Pilsner malt to replace and it's sitting right at 10SRM according to Beersmith. That's the lower end of the style per BJCP, but I drank Alt in Deutscheland for a year and a half, so I know better - I never had one over there that wasn't quite a bit darker. It shouldn't have any roastiness, so I need something dark as %$&& that will add a little color with no other effect. I guess I'll start a thread. End ramble - good luck.

 

You could also try a different yeast that accentuates malt flavor more and might even have a lower attenuation rate. Putting in more specialty grains would help also.

 

I'm going to be experimenting with Melanoidin malt in my next IPA, maybe 10% of the grain bill.
More info:
http://www.brew-dudes.com/melanoidin-malt/226

For an extract batch, shoot for 1/2 to 3/4 pounds. I'd go with a grain over maltodextrine to add body every time. Steeping grains make a HUGE difference in taste, freshness, and body.

+1 on the yeast strain idea as well!

 

My current batch included 5% melanoidin (the first time I've used it). After reading quite a few warnings about how potent it is, I decided against 10%. The first test bottle will be cracked open either tomorrow or Sunday - I'll let you know how it turns out. If there's not a big jump in malt profile at 5%, it may well be fine to go straight in at 10%...

 

You want a yeast with relatively low attenuation, like some English strains.
Whitelabs WLP-002 English Ale, liquid, attenuation, 63-70%
Danstar Windsor Ale - didn't see a percentage, but Danstar calls it low attenuatiion. This is a powder. Very easy to use, and starts quick and easy. One pack, rehydrated in an Erlenmeyer 90-100 F boiled water for an hour, into 5 gallons of wort. Easier and more reliable than liquids, IMO. We just used this on a big IPA - it exploded.
Danstar Nottingham is their clean, high attenuation yeast, also quick and explosive.
Wyeast liquids are harder to gauge because they pretty much claim high att. for everything, but their American Ale 2 is a high body version of 1056.
The flip side is that these yeasts tend to make a more estery beer - some like that, some don't. Personally, I'd look to the grain bill and unfermentables for body without the funky English flavor - strictly a matter of taste.

 

After tasting my sample, I think you're probably fine to go in at 10% melanoidin.

 

Let us know how it turns out! Have fun brewing.

There's nothing better than calling in sick to work and brewing all day!