Hi Finski,
I can only go on my own personal experience in regards to what you see with a larger aperture, as I started off with a 16inch dob down to 8 inches. I have found deep sky objects to be brighter and easier to pick out details when it comes to planets in particular.
The limiting factor for me was the weight of the scopes became a issue for me greater than 10 inches.
In terms of computerised it helps with short videos of planets and not having to nudge at higher magnifications. When I had people over to view it helped to keep the objects centred and locating objects is easier if you want to use it
I found others do not have the same attention span and patience as yourself hunting for objects, especially in surburbia.
Anything that speeds things up to increase your viewing time I think is a worthwhile investment.
If you are not in a rush I have found grabbing a scope second hand has been cost effective. Eyepieces are a different thing, they tend to hold their values.
Since you have 6 inch dob , I would recommend a 10inch or 12inch if you can manage it or use a trolley. The type of scopes in that range will probably be a dob or sct with varying costs.
Hope it helps,
M11
PS - Only my experience and people's mileage will vary