what part of "legion" dont YOU seem to get?
Oh I "get" the Legion that is modeled after the Roman Legion.
legion is a military term for number of soldiers.....they had legionares during the republic as well.
Legion from Latin legio "military levy, conscription," from legere "to choose".
The use of the term legion did not ended with Roman Empire but its pretty clear the purpose of its later use (like the French Foreign Legion that is certainly NOT a term for a number of soldiers).
Rome had its biggest expansions were in fact under the republic and not the caezars who added smaller territories and then ended up in a rope-a-dope with the surrounding powers.
I never claimed such, Julius Caesar was never Emperor even if he was named Dictator Perpetuo.
the roman empire wasnt nearly as successful as the roman republic which was its best mode.
I also did not claimed as such, even if I would point out the Republic had a lot of problems and such problems lead to the Empire that was more effective as even if they still had bickering Senators and Consuls at least someone was holding their leash.
emperors spread the army to thin,
So most of the conquests were done during the Republic and yet the Emperors "spread the Army too thin"?
And here is were I say "no", the Roman Empire borders eventually became stable and Pax Romana took hold, without enemies you dont need a army so they started to cut expenses on it.
wasted resources in personal projects etc.
I am having a hard time to think what was a "personal project" as I really have no idea, I know Nero did rebuild Rome but its not as if the place did not burn to the ground.
very few of the emperors were actually beneficial to Rome. the rest were either downright destructive or at best didnt effect anything much.
This is were you are going well off, nobody is claiming that the Roman Emperors single handed handled the Empire.
Following up to Augustus was a tough act, also "the rest"? the Nerva–Antonine dynasty were the term "Five Good Emperors" comes from (there were 7, one died with the Plague that leaves 6 and since Commodus was the last ...)? Sure a LOT were assassinated or killed (by the Praetorian Guard or the Legion) but still MANY died of natural causes.
Going back you still have to understand Caesar's Legion is based on the Roman Legion
of Julius Caesar time, a anology would be trying to create a society based on George S. Patton Biography ... you would get something that would be similar to the US Army during World War II but not the United States of America of that period.