Gearing on drivetrains
Your only alternative is to get a crankset with a different BCD (bolt circle diameter). You have a 110mm bcd, and while it is possible to use a 33t gear on
the front, it won't help much and they are difficult and expensive to find. 

IMHO, if 34/32 is not low enough, then by far the most straightforward thing to do is go to a triple.

However, that is not your only choice. You could try using various 2x cranks from the MTB world. The problem there is the large ring size is limited and getting the
shifting working correctly can be tricky. 42/28 is probably the best you can do, although with some searching you might be able to get a big ring up to 48t. Shifting that big a gap will also present problems. 

There are these cranks which offer a compromise btw Road and MTB doubles. 

http://store.velo-orange.com/index.php/components/cranksets/grand-cru-50-4bcd-crankset-mkii.html

They have a 50.4 BCD and can use chainrings from 28t to 62t. The problem is they don't shift quite as smoothly as more modern chain rings with ramps. 

Middleburn also makes some double cranks with BCD smaller than 110, 

http://www.middleburn.co.uk/products/cranks/road-touring-cyclo-x

Surly's Mr Whirly cranksets also come with "spiders" that could be used to 
create a smaller crankset up front. 

http://surlybikes.com/parts/drivetrain/mr_whirly_crank

Lastly, you could consider expanding the gearing out back. There are Mountain Cassettes that go up to 42t these days. You'd likely need a new rear derailleur, I'm not sure about the shifting.  

http://www.pricepoint.com/Brand/Wolf-Tooth/Wolf-Tooth-42T-GC-Cog-for-Shimano.axd?gclid=COvqhoaY9cACFcRbfgodLz0AwQ

All in all, going to a triple is by far the simplest and will actually get the gears you need. All any of these solutions provide is at best 2 more lower gears. 

I highly recommend switching to a 110/74 triple with something like a 24/36/48. 
If you do get a "road" triple with the standard 30/42/53 gearing, swap the inner 30 for a 26t.