I'm wondering if there any reliable way to get some skill point, so far I only manage to get 2 skill after more than 4 hours of game so I'm not getting into the size sacrifice any time soon with how slow I progres anyway
Leveling up is the basic way to get them. You can sacrifice your levels to keep your level low so that you level faster and then use the mini game buffs to keep some strength while being level 0 all the time. Also using the essence to keep your levels while staying at level 0… A few quests will give you the blue ability crystal which gives you 10 skill points. Like doing the Lich quest and then talking the potion shop NPC after you kill him… But then a few dungeons give them as a more common drop like the ruins or the gator mine I think. You can also use console commands to spawn ability crystals, but that’s cheating :P
To add to what proflational said, note that sacrificing Size gives a lot more ability points than the others. Just keep sacrificing and stay at level 1 or 2 (or 10 or 20, because I like multiples of 10).
Not 0, since you should keep at least one stat point in a "main" stat to make the Strange Fruit bonus go to the stats you want. Don't worry about increasing the ability tree for the stat you like the most. They're mostly disconnected mechanics, just grab what's useful.