ah ask 10 turners and all that
and get 15 answers
When I teach I introduce students to what I believe are the necessary tools to complete every project in turning other than an under cut hollow form.
For this I recommend
19 mm Spindle roughing gouge
10 mm Bowl gouge
10 mm spindle gouge
19 mm rolled edge skew. Personally I find the oval unstable in use to start out with.
6 mm Parting tool
25 mm round nose scraper
25 mm Square scraper
(or get the 25 mm shear scraper which has the convex and concave option in one which saves money and is a better option as it is a round bar tool so stable during shear scraping.
Now I hear what people say about scrapers, but they have been around as long as turning itself and when starting out turning they can be a good 'go to' option when getting to grips with the bowl gouge and in many cases they are used by the most advance turners for certain situations, watch Steve Jones's videos to see this.
I advocate and explain that with practice they will be able to get a smooth curve and a fine finish in bowl turning with a gouge and to practice to achieve this.
However many starting out will not be able to get the practice that many of us do, frustration can creep due to poor surface finish due to bevel rubbing problems so I always explain the use of scrapers as an option along with the positives and negatives as with all tools.
Indeed I and many others can turn a complete bowl using only a 10 mm bowl gouge with long grind, including finishing and shear scraping cuts. This is not how I would start out teaching as it is not the most suitable option for a beginner. Scrapers are an important part of our arsenal.
Just my thoughts, we all do it a bit differently once we get into the swing of things but foundation knowledge for me should be a constant.