When any of the conjunction particles that carry the meaning of 'if' (たら, ば, or と) are paired with the い-Adjective, いい, they will express the desired result of the speaker. These all translate to 'it would be nice if (A)'. However, the speaker's level of certainty about the result being 'good' will change slightly, depending on the particle.
ばいい - Hypothetically, (A) happening would be good. (Lowest strength/certainty)
たらいい - When (A) happens, it will be good. (Medium strength/certainty)
といい - The result of (A) is good. (Strongest/most certain)
To use ば, たら, or といい, first add the conjunction particle to the end of any verb, and then attach the い-Adjective, いい.

• 明日（あした）までに届（とど）けばいいんだけど、多分（たぶん）届（とど）かないと思（おも）う。
  It would be good if it gets delivered by tomorrow, but I don't think it will.
• 私（わたし）もあんなに早（はや）く走（はし）れたらいいな。
  It would be nice if I could also run that fast.
• 来年（らいねん）は海外（かいがい）旅行（りょこう）に行（い）けるといいね。
  It would be nice if we could travel abroad next year, right?