Higher troop level, more powerful they are. AFAICT, it is not linear.

This is particularly noticeable on defense.

It is often said only use t1 on (tile) attacks or for yielding - troops are going be destroyed, and points for >t1 go up rapidly. If you are getting more points than they are when you attack with t1, keep attacking with t1. When you are attacked on t1 you will lose less points when they die. Points there are not linear.

It is arguable to skip t2-t5. Now, perhaps even t6. There is so much building and training to do, you can focus on that while your work on the studies. [And t7 studies brings enhanced bonuses against t1-t4 bringing annihilation even more prevalently. It won't matter what level troops you have, they're going to be destroyed - cheaper to lose and retrain t1's than greater.]

Even if you're not ready to battle with t6/7 yet, having them unlocked lets you train them for the points in the mean time, and lets you build up the number of troops while you work on the studies.

It is also arguable to not raise your palace beyond 26, or 31, until you have completed everything else to that point - going beyond these raises your league level, which also changes the rewards given. e.g. t6 studies requires Pearls (IIRC) and >26 building requires Platinum. In those leagues, checkpoints reward with those. Go to p32 without having those done, where Ingots and Selenium are now given, and you will be scrambling for Pearls and Platinum to be able to complete things.

Studies go to different levels. Many 10, many 15. Some 9, others / unlock only the 1.

Alchemical is just another path to improving your troop's offense and defense. In the end, it doesn't matter by how much - it's about whether your opponent does or not, to have an advantage over you or not. Thus, to not give them the advantage, you have to do them.

I stopped after doing my troop type and scouts ... but it has recently occurred to me I could do the health and defense of the other troop types to make such enemy's troops less effective. Still mulling over that ... I don't have those troops, so nothing to health / defense / offense bonus. And it gets VERY expensive - and there are no event points for doing so.

IIUC, https://throne.help/en/resources/troop_upgrades/ shows you what you get with them.

Post a followup for anything not addressed - I don't think I follow all of your message as you intended.