1)
Why does it say "Machshevos Shalom v'Lo l'Ra'ah"?
1.
Malbim: Shalom can be bad, e.g. the exile of Tzidkiyah was delayed, and this was bad, like the parable of the two baskets of figs (24:2-10). If a fig is not picked when it first ripens, it gets wormy.)
2)
What is "Acharis v'Tikvah"?
1.
Radak: It is a good end like you hope for.
2.
Malbim: Acharis is to last in the land. Until that time you will have Tikvah (hope).