Surround speaker upgrades / options

[Schizophonic]

This is my current setup in the living room, running a 5.1.2 setup.

From the picture below as you can see I have some ceiling wall mounter speakers but the left channel has now become distorted and needs to be replaced.

Within a reasonable budget (£150ish) I'm looking to have some speakers lower down but on stands or even wall mounted but head height. I have so many concerns like is that speaker placement even suitable if I plan to have it or should I find something with taller placement? I need to know what options I have really? Also I dont mind going for the 2nd hand option around the same budget.

2nd picture is just for reference with the front of the setup.

 

[Schizophonic]

You need to raise the center it's way too low

Your left and rights are way too close.

Since you're close to back wall I'd use bipole speakers instead of regular speakers.

Thanks for the suggestions in with bipole speakers. Any recommendations which ones? What does the bipole have over regular speakers?

 

[Schizophonic]

There's a pair of BP-1X speakers on the auction site now. I'd put in a lower offer

The mrs is gonna kill me if i put them up on the wall lol. I was hoping for something a bit more low profile.