I've been out of Texas a long time. However, I use to enjoy Round Top - nice wildflowers, Royer's was a very good restaurant, I've heard Outpost @ Cedar Creek is a nice Bed & Breakfast.
usually the highway between Fredericksburg and Mason is covered with them, especially the last 12-13 miles as you get closer to Mason--then between Mason and Menard is also a good place
Willow City Loop out north of Fredericksburg on the way to E. Rock ought to be spectacular this year with all the rain.
Willow City is a funky little Luckenbach/Terlingua town without a reputation at the end or beginning of the loop's south side. The loop takes you through some karst territory with 400-600 foot topography trending north, pretty much the largest hills in central Texas.
We usually want to go about now, but up a thousand feet higher than Austin flowers can be a couple of weeks behind where they are here. So we will wait until late April.
Sunny days nearing sunset will give you excellent contrast and shadows against fine grasses and flowers.
The Blue Bonnet Cafe is always packed in Marble Falls. That is another nice area to drive around in. I believe Longhor Caverns is in the vicinity. If you approach it from the West, you should be able to see a castle someone built out there.
The Llano Uplift is like the Balcones uplift on steroids, so do some reading on the geology of the region in advance for a more densly satisfying drive through the Hill Country.
I've driven a lot of miles photographing wildflowers this last week - around Mason/Llano. I must be spoiled, bc I was dissappointed with the Willow City Loop. There were a few nice fields, but I took a client out there yesterday (his request) and then to some areas around Mason and he was floored at some of the fields near Mason (south end of Old Keyserville Rd) - no comparison to WCL. Plus, WCL was a beating with the traffic - and this on a Monday!
Hwy 152 bw Mason/Llano is pretty good - especially near Castell. There is also a road connecting to 29 near Mason called (something like) Art Hedwigg Road or something like that - that currently has the most amazing bluebonnet fields I've seen thus far, but they are at the end of peak so you'd better get there in the next day or two (I was there Sunday and Monday getting some images). Just incredible lakes of blue with Mesquite and cacti swimming along.
We have two B&B's in F'burg (both on Main Street). Keidel Inn & Gasthaus has 3 suites & is located across the street from the Nimitz Musuem. Our family has owned this property for 100+ years & we just reopened it in March after doing some extensive work. Our other B&B we opened in October 2008 & is called Legacy Suite (just two blocks down Main Street from Keidel Inn). Here's the link to check us out: The Link The Link