Do NOT engage in "consulate shopping" as this is the reddest of red flags with respect to malafide intent. The Spanish, Greeks, French or whichever other Schengen consulate you apply to will have details of your refused Italian application via the SIS system so there is absolutely no benefit in this.

Your best option is to submit a new application to the Italians with details of your new job and of the additional funds available. Also include a cover letter explaining in brief an overview of the changed circumstances since your original application. Unless there are other issues with the application that have not been disclosed, this should be sufficient to overcome a presumption of immigrant intent.