best strategy doing a large copy and using indexes

I have a table with 7 individual indexes (it models an object store
with different types) and need to copy large data lists into this
table regularly. I'm using COPY for it but it is unacceptable slow
(4min for 1000 rows on a Linux/PII-400). I'm anticipating more than
20000 rows to copy. What combination of the following options is the
best strategy to make this more efficient?

a) drop indexes before COPY and recreate them after COPY

b) put COPY in a transaction

c) do VACUUM before (or after?)

d) do VACUUM ANALYZE before (or after?)

e) COPY to temp table and then make an INSERT SELECT FROM temp table

f) anything else


I'm using -f for the backend already.

Dirk