In short...yes you could get away without running a SERM... but I would run one just to be safe if you can get your hands on it. However, I do know of more then one guy who has ran a halo only cycle without a SERM and bounced back just fine with blood work to prove it. But be aware that just because they came back fine does not mean you will, everyone reacts differently.
Your pct looks good minus the SERM, you could look into CEL PCT assist also.