When you say you want a smaller guitar, are you looking for just a smaller body or also smaller scale length for your fretting hand? And if you want a smaller scale length, how much smaller? If you want more guitar feel and sound with just a slightly smaller scale, you can go with the GS Mini, which is 23.5" scale. But for some, still feels a bit wide coming from the ukulele. The Baby Taylor is 22-3/4" scale, or the Martin LX1 is about 23".
If you are looking at something more in the baritone ukulele range scale 20-21.x, then some options below. Also, Kinnard makes an Octave guitar, which as the same scale length, 17" as a tenor. You can check his website.
Here are 3 options for some smaller "guilele range" small guitars. I have been interested in trying one, so have been doing a little researching to find one
1. I just pulled the trigger on a used Kinnard Kiku - Cocobolo/Spruce. Cant speak to it yet, as I have not received it yet. But, something you can look into if you want to commission a custom one or buy one that comes up somewhere. I bought mine from HMS. From all the Kinnard ukes I have heard, they have some great sound.
Kinnard Kiku -
https://vimeo.com/135114553
2. Or Lichty also makes a kiku version that sounds nice.
https://www.youtube.com/watch?v=Mb3ma---5nc
And he makes another model called the baby bard version that is supposed to be just slightly bigger than a baritone uke body.
http://lichtyguitars.com/models/baby-bard/
3. Also, you may want to check out Pono
Pono -
http://ponoguitar.com/index.php/mode....html?___SID=U
Uku Li'i 6 String - Small body 6 string: Overall Length 33 inches. 11 1/4" wide body, 21.4" scale.
- UL-10 Acacia top, back, and sides. Tamarind binding, abalone rosette, solid headstock, gloss finish. $1099
- UL-20 Mahogany back and sides. Spruce or Cedar top. Rosewood binding, abalone rosette, solid headstock, gloss finish $1099
- UL-30 Rosewood back and sides. Spruce or Cedar top. Maple binding, abalone rosette, solid headstock, gloss finish $1199
- UL-40 Ebony back and sides. Spruce or Cedar top. Maple binding, abalone rosette, solid headstock, gloss finish $1499