New places to go in Guatemala

Consider exploring Huehuetenango (awesome state, cool city in some ways), Nebaj (the Ixil triangle), or maybe towns on Atitlan that you've never been to. Maybe figure out which town festivals coincide with your trip and visit them in Quiche or Coban, etc. Laguna Lachua? Laguna Brava?

I just did a great road trip with my kids last month through the Rio Dulce and the Alta Verapaz. Four nights with stops at Finca Paraiso, El Boqueron canyon, Las Conchas waterfalls, Candelaria caves, and Laguna Lachua. All great destinations and fantastic scenery along the way.

I 2nd the Ixil Triangle. Maybe you could do a multi-day hike between there and Todos Santos with Guias Ixiles.
http://nebaj.com/guiasixiles.html

The Cuchumatanes/Huehuetenango has been on my list for a long time, so if I were you I'd definitely make a point of spending some time there. The area around Coban--and the Verapaces generally--would certainly be worth looking into as well.

And even if Livingston isn't your speed, the whole Rio Dulce/Izabal area is really beautiful and has a fascinating history, with a lot of small Spanish and Mayan-speaking communities that make for great off-the-beaten-path travel.

You may also enjoy poking around some lesser-visited parts of the Peten. San Jose, on the western side of Lake Peten Itza, has a neat community-run tourism operation and there's an important archaeological site nearby (Motul de San Jose). Yaxha is one of my favorite ruins in Guatemala, and can easily be accessed from Flores. If you want to get a bit further afield, you might consider a visit to the Guacamayas research station and El Peru-Waka, near Paso Caballos.

Consider Honduras, great country.

Thanks for all the suggestions. I think Honduras (along with Nicaragua) will be a later trip when I have the time to devote to it. I have quite an attachment to Guatemala and really want to go back.

But yes, great suggestions. Maybe I'll do an itinerary like this:

Day 1 - Antigua
Day 2-5 Rio Dulce Area
Day 6 - Antigua or Guatemala City
Day 7-13 El Salvador (San Salvador & Suchitoto)
Day 14 - Antigua
Day 15-17 - Lake Atitlan
Day 18-22 Nebaj area (May replace this with Huehuetenango... In the contest between Huehue highlands and Nebaj area highlands, which wins?)
Day 23-27 Xela area (I have spent months in Xela and want to spend a good deal of time here)
Day 28-31 - some buffer time built in here.

Recommendation of beaches in Guatemala? I know it's not really Guatemala's thing but I have really enjoyed my time in Monterrico and Champerico.

I like Tulate for a beach break. Easy to get to from Xela. Gregbul's trip sounds great - def better if you have a car but doable by bus. I like Nebaj and surrounds more than Todos Santos but neither may appeal too much of you're not into hiking. Laguna Lachua is great. Don't discount Livingston on language grounds alone - it's definitely a Spanish speaking town.