That is a fair bit of dust on the diagonal, although I usually find it's worse in a close-up photo than in real life, so try it an see. The moon is a good place to start and near full right now.
In the 2nd photo there are a couple of vertical marks. Are they on the front corrector or the mirror?
A lower power eyepiece (EP) would be good (40 - 42mm ideally, as Brian said). Try to keep above 35x magnification as below that you may get intrusion of the secondary into the image (it'll depend a bit on the size of the secondary). Magnification is just the ratio of focal lengths, so mag = 1900 mm divided by X mm, where X is the EP focal length.
There are as many opinions on EPs as there are astronomers! The focal ratio of your scope is fairly gentle on eyepieces, so you will benefit less from exotic/expensive designs. Having said that, at lower power, you may be more interested in a wider field than a regular plossl will give ... or maybe not. The best bet is to join a local club (usually very cheap) and try some EPs in your scope at one of their viewing nights - that'll give you an idea of how much importance you place on field-of-view (FoV).
For automation, you can buy a motorised/go-to mount (sometimes here in the classifieds or other trade sites). But, give it a go on the existing mount. A go-to mount will set you back quite a bit, so make sure you're happy with the optical tube asembly (OTA, a.k.a. telescope) first before spending more money. Besides, learning to "drive a manual" has its own satisfaction ... and it'll make you learn the sky, which is valuable ... before you sell your soul and get a go-to!
Edit: Posted before seeing Brian's latest reply (I type s-l-o-w-l-y).