The length of poles is a personal preference and should be based on how you can place them in four boat. Most tightline situations with 4 poles would be 2 on one side of a front mounted trolling motor and 2 on the other side. If the rod holder can be mounted square in the front of the boat then a 4 place setup will work.
Some guys like 2, 14 ft. poles out the front and 2 , 12 ft poles beside them. Personal preference really. I have used 16's out the front with 14's beside them and 4 12's beside them in an 8 rod set up, but I have gone back to 8 12 foot rods.
I use Wally Marshall's so someone else will have to advise on the B&M poles.
I like reels you can pull line from easily for tight linning. ( for depth control) but the reels you suggest should work fine.
I have the same problem with the bobber stop. I have used every kind made and everyone of them with any use will hang in the eye if you try to fish any depth. I have saw reports where guys swear by them, but they do not work for me. If you take a pair of pliers and really tighten the bobber stop line it will not slip. It will catch in the eye no matter how close you trim it.
Tightlining is the term used for vertical fishing by slow trolling. It is usually done with a slip sinker,bead, swivel and 12 to 18 inch leader. A plain hook or jig is attached to the leader. Some also use a double hook set up. Depending on the depth fished the fish can be put in the boat without reeling. The rig can be employed in 30 plus feet of water as well as 2 ft of water. In the first the fish has to be reeled in. In the second line has to be released to land the fish.
Others use just a jig or split shot and jig. I call that slow trolling and not tightlining.
Vertical jigging would be done with pole in hand over brush or some other type structure. A jig, kentucky rig, or drop shot rig could be used. A search of the forum will yield information on kentucky rig, drop shot and bobber stop.
Some folks use slip float ( unattached) on their line when tightlining. They watch that instead of the rod tip. I have never used that technique.
If you used an attached float with a jig or split shot and jig under it you would in my opinon be slow trolling with a cork or float and not tight linning.
Good luck