Adj + 了 + (一)点儿 (a bit too)

"A bit too big"

• Adj + (completed / change)了le + (one / a一yī)erhua variant of 点点儿diǎn ér = "a bit too …" — a mild complaint about excess.
• see 大夫大dà(completed / change)了leerhua variant of 点点儿diǎn ér = "a bit too big"; expensive贵guì(completed / change)了leerhua variant of 点点儿diǎn ér = "a touch too pricey".
• The (completed / change)了le signals it's gone past what you wanted.

Adj + (completed / change)了le + (one / a一yī)erhua variant of 点点儿diǎn ér

• (completed / change)了le + erhua variant of 点点儿diǎn ér after the adjective = "(too) … by a bit".

this这zhè(measure word)件jiànclothes衣服yī fubig大dà了lea bit点儿diǎnr。

• see 大夫大dà(completed / change)了leerhua variant of 点点儿diǎn ér = "it's a bit too big."

Mild complaint

• It quietly says "more than ideal" — like a little有点yǒu diǎn before the adjective.

Recap

Read the full reference: HSK 5 grammar — Adjectives.