Let me give you some hints to make the map look better:
1. Those autotiles you use for the treetops are bushes.

The best way too create lots of trees in a line is to start on the second layer. Place the lowest row of tiles. Build up by placing the next row above it, then the next one, until you've done them all. If a tile must go over another, only do that tile on the third layer, so you have more space. If it still doesn't fit, choose that tile as the graphic of an event (fourth layer). BTW, start from the top while doing this.
2. Those colors don't really go with each other. Maybe you should try to change the colors of those auto-tiles. Elseway, try to fit a pre-made jungle tileset for RMXP. I've seen one on RRR.
3. It's kinda hard too say... The map is empty... But it's also full. You are using too much of the same decoration. Try to put some bushes near the trees first. To make paths, use the dirt or shadow autotiles. Those logs, try to bring more difference and place them further away from each other. It would also look nicer if you place those tree bases next to one of the ends of the logs. Also, those trees. Try to place more of them near all the other trees (bushes).
4. The paths and the water... The paths, if they are nature-made keep them like they are now, but if they are man-made, make them more linear. The water is good but if you want to, you can make some small streams coming from it and use the logs as bridges.
I think that was it. Remember, these are only some hints. You don't have too use them, if you don't want to.
Last thing I want to say is good going, and gl.