I need some experienced advice to decide purchase again another D7000.

i love my d7000 its sharp as a tack with my 70-200 vr lens. i havent used the 18-200 but have heard alot on how soft it is because of the range. i recommend getting good glass with the 7000

Keep your D7000, its an amazing camera.  Your problem is your glass.  Good glass is an absolute must

I have a D7000 with the 18-200 VR2 'travel lens'. I don't recommend that lens for landscapes though - that sort of vast focal range is never going to give you amazing results. I find the lens is soft. But it is a great all-in-one lens if you want to travel super light and not miss a shot. It's a fun lens.

I don't like changing lenses all the time and only have one body: I find myself using the 24-70 mostly, which gives me the sharpness I need, though lacks the wider and tele end the 'travel lens' has. It also gives far better contrast, colours... it's like having a new camera. If you're images aren't coming out sharp, its you and/or your lens, not the camera. Get decent glass: if you're on a budget get a manual wide angle Nikon prime for landscape. If you try the 70-200 VR or other pro lenses you'll not want to hand them back. 

The D7000 colours come out a little muted straight out of the camera in RAW, but that's easily adjusted in Lightroom. You don't shoot JPG I take it. D300s replacement for probably near on $2000: why not get a D800 full frame for $1000 more.