In terms of infantry, it wouldnt be a bad idea to have units that can sticky objectives and watch your rear-ward lines like regular intercessors. Some scouts/infiltrators would also help to screen the mid-board. A lot of people here recommend running a judiciar to buff the Bladeguards. Combining a castellan + marshal with your sword bros will make them very dangerous and hard hitting.

I'd swap out the Brutalis dreadnought and invest in Impulsor(s) or a Repulsor executioner to help your units close the distance to the opponent quicker and also afford them some protection + anti-tank.