I think that it may be an idea to go through my marker float and spod set-up again.
For years I used a specific spod rod, and a specific marker rod, however plenty of bankside features have meant that I can now use one rod and spod rod for both.
My standard marker rod set-up is 50lb 0.36mm braided line, with a 30lb Amnesia leader, a run ring and an Amnesia lead link of around 150mm, or 6inches, and the leader going to a ball bearing swivel and a Breakaway spinlink clip to take the float. Don't forget a buffer bead or couple of large beads.
I vary the float size on distance needed to cast, visibility etc, so I would use the ESP Mini Marker for close in with a 2.5 or 3oz lead, going to a big (both found) Korda or MCF float for longer distance with a 4 or even 5oz lead.
If I switch to Spombing or spodding then I attach that to the end of the line spinlink clip, and clip the lead link clip through the spod swivel and the other spin link.
The leader gives enough elasticity not to crack off the spod, and at 4turns on the reel and casting drop does not reduce the sensitivity of the marker float set-up. The lead link I think also allows the float to come up most of the time, it is down to feel whether you can put a bait in it.
I have found numerous spods and marker floats, and every single one was attached straight through to braid, so the mono leader, I think is important, unless you go to silly braid strength, like 80lb!