Create F5 LTM Content for http / https via port 8080

it seems that with this iRule, I can create one content using wild card service port (1.1.1.1:0) with client SSL and this iRule will cut my current 3 contents into one (taking care of 80, 8080, 443).. CORRECT?

Correct. One VIP with a client SSL profile. The iRule will send the traffic to the correct server pool based on incoming port and optionally disable the SSL profile if it's not a port 443 request.

does it matter what port I use for backend service? perhaps wildcard for that as well?

If you use a wildcard port, you'll also likely disable port translation on the VIP, meaning the request port will be what's used on the server side. If that's not the case, make sure port translation is enabled and create a single pool or three separate pools depending on where you want the traffic to go based on the client's request port.