I'll put in a vote for Zhuyin:

- more consistent (no confusing between the two sounds for "u" for example).

- better IMEs - you can filter characters by tone, impossible to do with Google Pinyin for example.

- can be used to type Simplified and Traditional

- no interference/preconceptions from other languages written in the latin alphabet.

Moving everything to pinyin probably would introduce a different set of difficulties for a foreigner: while a native Chinese speaker knows the spoken language and context well enough to disambiguate homophones, it's unlikely a Chinese learner would have the same ability.