Especially the elephant grass pieces look magnificent! What a you using for EG? And those paths through them look very nice.
When applying static grass I would recommend add it it on more numerous and more irregular sized smaller area to make it look more natural.
I think the smaller bases (for the palms) do not blend in well with the other pieces just because of the size looks kinda odd with the rest of them. Upping the size to 3-4 times and adding a second or third palm should do the trick -at least I think it worked with my tree bases.
For example the one on the lower right of this pic with a bigger base and bigger palm works noticeably better. Mot likely as it look more naturalistic with more base and more terrain bits. link
Years ago I was amazed to find out that plenty of the Vietnamese soil has a distinctive reddish hue. Certainly can't apply to everywhere though, right?
Lastly, try giving the clump foliage and static grass some quick drybrushing too; it'll improve the look even more with rather minimal effort.
I've actually even painted the plastic plants to make them look bit less, erm, plasticky but that is rather big a chore and not all that necessary.
Good job and carry on!