Well, preference in tone is very subjective and ultimately will depend on you and your tastes. I have seen the old blues guys finger pick on everything from jumbos and dreads to small 0-size guitars. Their tonewoods of choice have also been anything from rosewood to mahogany to maple to ash and probably many more. For example, Dave van Ronk for most of his career preferred an F50R while Mississippi John Hurt in his later years jammed out on an F30. Pretty different, but great country blues came out of both. A question I always ask someone is what they want out of their guitar. Deep full bass? Balance? Tight midrange? Are you going to sing with the guitar unplugged? And if so, do you have a loud voice?
So here is my personal experience since I would say almost 70% of what I play is country blues. I used to have a GAD 30 which had mahogany back and sides and was a fun guitar for the blues. I wanted the emphasis on the midrange with the twang of mahogany. Good guitar, but some braces came loose, and through the warranty, Guild replaced it with a GAD 30R. Well, this has an elegant sound quite typical of rosewood. Loud, full, many overtones, sounds like a harp. The sound in my opinion is that fit for a king, but not the sound I was going for in terms of country blues. During this time a had acquired a D25. This has an archback mahogany b/s over spruce. Great full sound, booming bass, booming bass, and booming bass. It has the hog sound I was wanted. The guitar, while great, is not balanced and sometimes a thumping bass will overpower the melody played on the high strings. I also find dreads to be uncomfortable after long periods of playing. Sooooo, I acquired a Martin 000-15 earlier this year. Not a Guild but a great blues guitar. All hog and yes it sounds like an all hog guitar. It has my preferred size and sound so I play most of my country blues on it.
Now, if I had endless amounts of money at my disposal and was looking for a Guild for some good old fashion country pickin'......I would get an F30. It has the mahogany twang I enjoy so much and has a full sound. The ones I have played had the tone of my D25 but balanced. D25 is louder of course. I find them ideal for me since I sing while I play. I am not loud like van Ronk or a Gary Davis so a jumbo would drown me out. The F30 has a smaller sound so I do not have to strain my voice to be heard. The guitar is also small and comfortable for me so I can play until I decide to stop instead of being forced to due to discomfort.
Just keep in mind that some of the best blues music ever created came out of some of the crappiest instruments ever made. Good luck.