If Pennsylvania's insurance commissioner decides to approve the proposed merger between Independence Blue Cross and Highmark Inc., he should impose a raft of conditions designed to limit their market power, says the Republican-led Senate Banking and Insurance Comittee in draft resolutions scheduled to come for a committee vote. The decision on whether to approve the merger rests with Commissioner Joel Ario alone. But the committee has lots of opinions on what Ario should do, starting with a plea that he reject it.