Tilesets you use are not the problem with this terrain. It's the way it was used. If I must prove this myself by making a Lordaeron Summer terrain, I will. Besides, this terrain looks like it was done with the Village tileset. What makes this terrain look generally poor is main the lack of tile variation and poor tile placement. It looks very plain and doesn't really mix well where it should. To help variate the terrain more, lets talk about the first terrain shot uploaded of the Grassy Dirt path. What you should do is use a lot of dirt tile variations in there instead of grassy ones. Rough Dirt and Dirt are the two tiles that make roads look like used roads and stand out best as roads. If you want examples, I would recommend looking at melee maps made by Blizzard Entertainment such as "Booty Bay." Use those melee maps as your references. Learn from them. They can be very handy if you're a visual learner, rather than an auditorial one.
Another thing that makes this terrain poor is the lack of hill variation (Otherwise known or refered to as 'Height Variation') and its overall flatness. When making hills in terrains such as this, do not make the hills tall, but make them large in size (Use the biggest circle to place hills with) and when you're done placing a few or more of this hills in various areas of the map's terrain, be sure to make use of the 'Smooth' tool which is where the 'Raise' tool is in the Terrain Palette. Smoothing hills can be very, very helpful and useful. How? Well, one thing you must always keep in mind to never do when terraining hills or even mountains is to make sure they aren't pointy. Hills should never be pointy, no matter where the terrain is located. Mountains and cliffs are the only ones where that might be somewhat excusable, but still not recommended. When smoothing hills, be sure to hold down the Left-Click on your mouse rather than tapping it over and over. Tapping it seems to affect the hill more critically and I would suggest tapping Left-Click only if the hills is very tall; but even then, holding it down is still easier.
The doodad placement isn't so bad, actually, but it does look cluttered in a lot of these terrains. For example, the fountain. There are way too many flowers ON it. I would recommend placing then around the rim of the outer part of the fountain rather than in it where the water falls.
~Craka_J