Questions I can't resolve If OP did shoot RS on purpose and made up the intruder story to cover it up:
Why didn't Reeva call or text anyone if she was afraid of him and ran to the bathroom for safety?
If they had been arguing all evening would she or they stop and eat in the middle of a heated argument?
There was no mention of dishes in the sink, so did one of them wash the dishes during the argument?
If they had been arguing all evening why would Reeva stay?
If they had been arguing why did Security Guard Mr Baba not see the lights on or hear anything when he was doing his patrol around OP's house around 2am?
Why purposely make room dark then give Reeva a light source with the phone to get to the bathroom so he could see her?
Why would OP mention anything about the Jeans? if he had ripped jeans off her or out of her hands while RS was trying to put on why not fold up and put with other clothes. No one would be any the wiser?
If they had been arguing for hours during the evening, early morning why were there not multiple lights on?
If OP was standing outside the door screaming at her and possibly banging the door with the cricket bat a couple times before shooting why was Reeva standing so close to the door?
If they were arguing through the door as Nel states she would have had time to call or text someone. Why didn't she?
Why was there no blood or brain matter on the inside of Reeva's hand if her hand was up by her head in a defensive way?
Why purposely put Reeva on the far side of the bed? It only makes it harder to explain how she got out of bed and past him without him seeing her.
Why is the blue LED light a problem? When he went to sleep the lights were still on as Reeva was still up so it would not have been a bother until he woke up and was getting ready to go back to bed after messing with the fans that it would have bothered him.
The bathroom window had to be open otherwise how could anyone have heard anything?
If they were arguing in the bathroom why argue right next to an open window for neighbors to possibly hear?
If neighbour Estelle VanDer Merwe woke at 1:56a and heard a woman's voice that lasted about an hour why didn't Security Guard Baba hear anything or see any lights on shortly after 2am while patrolling past OP's house?
How could Reeva balance on magazine rack without the use of her hip for stability?
Why was there no blood in the magazine rack if she has spent time on top of it with a bleeding hip wound?
If they had been arguing all night moving around the house why would OP not have his prosthetics on? According to State he was on his stumps when broke door down and when shot through the door.
If they had been up all night arguing, why was the duvet on the floor? Why were the bed covers disturbed if they had never gone to bed?
Why would the duvet be laid out on the floor like a picnic blanket at the end of the bed?
If she was running away from him and he was so mad wanted to shoot her why wait until she got to the bathroom? Or at least start shooting before she got to the bathroom?
So many things that make no sense to me regarding the argument theory.