most of the features you want are coming. i do not know much about tea and herbs but while poking around the game files, I found a new item: a coffee plant! so it looks like that as well as other new items are in the works. I generally find lots of "work in progress" materials which gives me an idea of when something new is approaching
i also think that computer upgrades are inevitable so when the time comes then just do it, especially with laptops. You'll probably need it for other activities anyways besides gaming. fortunately the game runs great already so unless Red51 abandons OpenGL 4.5 (the standard that your video card likely supports) then i doubt your existing hardware will suddenly become incompatible due to a game update. at worse, the game might slow down due to added NPC behavior, physics, better lighting and weather effects. all that stuff can likely be turned down a bit to make the game run faster.