I would way rather standardize the sounds like how Japanese does it (mostly) than have accents. I've never liked accents. I'm considering learning Ido over Esperanto because of this very issue.
Most people don’t know this but a lot of Japanese words have pitch accents that you need a dictionary to learn if you don’t learn the word audibly and the accents are not in the English/Japanese dictionaries, only in specialized Japanese/Japanese dictionaries.
When Chinese speakers learn Japanese they do well at learning it because it’s similar to Chinese pitch.
Esperanto doesn't have accents that emphasise stress the same way other langauges do. The little markers over the characters indicate that it's a completely different letter with a completely different vowel/consonant sound (and they have their own entries in the alphabet).
For example, "Co" would be pronounced like "Tso", whereas "Ĉo" would be pronounced like "Cho".
Pronunciation is completely standardised, with stress (almost?) always placed on the penultimate syllable.