Preparation for hardboard – understanding the questions

I usually paint on hardboard/masonite. I want to strengthen my conservation preparation which includes: a) Best techniques /materials; b) Understanding the questions and answers. 
I have been recommended Zinsser Cover Stain (VT Styrenated Modified Alkyd, Calcium Carbonate, Magnesium Silicate, Titanium Dioxide.) It would be really simple if it worked. But I’d definitely take proven methods over ease of use and possibilities. 

I’m trying to understand the questions. 

(1. The painting surface: (canvas, board, plaster wall) needs to be resistant to movement (expansion/contraction or bending), moisture, degradation (breaking down of the material) or release of chemicals. For masonite I build a cradle to keep it firm. Sometimes they need sealing. Chemical stability is a plus.
2. Barrier (size/etc): Some surfaces need sealing to minimise moisture absorption, moulds, etc and to stop it leaching chemicals into the painting. This barrier is best if it’s chemically stable including pH neutral. 
3. Ground: Oil paints need ‘tooth’ to grip a surface for a) Easier laying of paint; b) Sufficient adhesion to avoid peeling down the track. Best grounds will be very stable so that they don’t leach chemicals or react with the oil or the pigments, and stable so they don’t break down. All the ingredients. It also shouldn’t be too absorbent of either pigment or oil.
Questions:
I’m trying to understand the questions:
1. The painting surface: (canvas, board, plaster wall) needs to be resistant to movement (expansion/contraction or bending), moisture, degradation (breaking down of the material) or release of chemicals. For masonite I build a cradle to keep it firm. Sometimes they need sealing. Chemical stability is a plus.
2. Barrier (size/etc): Some surfaces need sealing to minimise moisture absorption, moulds, etc and to stop it leaching chemicals into the painting. This barrier is best if it’s chemically stable, including pH neutral. 
3. Ground: Oil paints need ‘tooth’ to grip a surface for a) Easier laying of paint; b) Sufficient adhesion to avoid peeling down the track. Best grounds will be very stable so that they don’t leach chemicals or react with the oil or the pigments, and stable so they don’t break down at molecular level, crack, movement etc. All the ingredients. It also shouldn’t be too absorbent of either pigment or oil. 
Questions: 1. What is the best proven preparation for board for conservation? 2. Where can I find the research-based material to build a basic understanding of the correct questions/criteria? Is my list close? 3.  Zinsser cover stain – I gather there are variations in VT Styrenated Modified Alkyds – is there a view on this product or similar? In some ways I’m interested in asking their technical team the right questions. The test of time it hasn’t passed, I know.