This an achieve post but hold some usefulness in it. But don't forget bounty is also like a hired service. Signature campaign organisers through campaign managers place and advert to prospective workers and employ them when the had fully all the required criteria. I don't think it's a wrong thing being on service board.
People also adverts there works(signature designers, escrow services, signature campaign management e.t.c) another board just for signature campaign alone would be unnecessary
I'd disagree. Signature Campaigns are usually an initiative by companies or projects whereas the other services you mention are users offering their work, there is a difference and it should be treated as such with it's own board, imo at least.
The false dichotomy can be pinpointed to this simplicity:
Signature campaign threads are bound by definition to contain a mass of posts in regards to registration. These replies are not guaranteed to result in a transactional event. You might argue that with other threads, the same is true, however the rate at which this occurs is quite gapped.
Mind, signature campaign threads also receive a higher number of bumps than other threads which are dependent on demand of the individual rather than of the group (of prospective campaigners, a larger set of the services space).
This pushes many of the non-campaign threads down. It would be as if you tried to offer a service in the Altcoin Bounty section: it would be buried. (Services is less insane than bounties but an analogue can be drawn)
