pgbench / compatibility with old(er) releases

Hi,

I'm running some tests comparing benchmarks on a range of versions,
going back to 8.0 (mostly because of curiosity, but actually for
practical reasons too).

I've decided to use the pgbench from 9.3, mostly to make the results
more comparable and because of features not available in older releases
(aggregation of transaction log, number of threads, ...), but this
causes issues on old releases because of features not available in the
really old releases - I've found these, so far:

(a) specifying fillfactor in CREATE TABLE
(b) DROP TABLE IF EXISTS
(c) application_name used for the connection

I do understand the versions up to 8.3 are unsupported (or soon will
be), but I think it's handy to be able to run current pgbench on those
versions. So I propose to:

(a) add --no-fillfactor that actually disables adding it to the
CREATE TABLE (now it adds default 100)

(b) add --no-appname that disables adding it to the connection (BTW
why not to allow custom appname? I'm thinking about multiple
pgbench instances running at the same time, or so, but on second
thought I've never done that.)

(c) do not use "IF EXISTS" but do that the old way (check if the
table exists in a separate command)

Opinions? Objections?

regards
Tomas