Okay I'll give you some suggestions, you can consider and test em or it may just open up some new ideas if nothing.
First lets break it down to what we have to deal with. We have GK engine of field presence and destruction which can combine with Tengu or itself or even rai-oh for Xyz. Furthermore it provides consistent tribute for Caius. So we cannot touch it.
Plant engine, well the decks name counts on it so we won't go from main deck idea.
Rai-oh as solid problem to your opponent and probably best light fodder you can find for this kind of build for BLS, also stays.
Gorz we need since deck lacks defense in means of heavy backrow so it also stays.
MAxx C pretty a staple this format and this deck has it even hard with 2 so maxing it out or cutting it more wont do any help.
We have a Reaper which has great eff, good defense power and is a fodder for Debris.... Still as we lack or space, his place is questionable here.
So now, we have 2 critical engines here that make trouble to consistency. BLS needs fodders and with this speed in deck and ceremonial mirror uses our necessary space. If we take out that bell we risk the flexibility of BLS summoning. Other critical engine is Debris. Bell counts also as fodder for his effect. But as reaper is one of the candidates to go out Debris might feel lonely.
Now let us consider which techs we could add in here. One thing is adding Gale and changing your extra deck so that you can add one Arcanite Magician. It is always good to abuse his effect and to get more use of GK engine here. But, gale might be hard choice since it will have to be normal summoned. So, at this point we come to Birdman. Tengu is his old pal so yea. Another thing here is that Birdman could replace debris very well in this deck. I mean when you use lonefire or dandy for spore eff, you hurt debris again, and somehow we need that extra space in here so badly, debris cannot summon anything good than blackrose but birdman will be able to do so. Combined with GKs he would be able to pull Arcanite magician too, and our consistency raises here.
Next thing is E-con. Great card but in here, space is more important so my suggestion would be to exclude it totally. I know it can do wonders with Caius and combine with many things but you just cant have everything possible in your deck and that it still keeps being consistent. Mind control would be enough
Next tech could be Dark Simorgh if you keep Debris. 5 Wind targets and also solid dark line up could make it no less chance for summon than BLS.
So at the end my suggestions are:
1st attempt:
-1 Debris
-1 Reaper
-2 E-Con
+1 BirdmanLike this we will have a 40cards deck. I know GK and Tengu are angry when they get multiple copies in hand but having 43 card deck just because they need less probability to be drawn in multiple amounts is not that smart either. Its a 2 edged sword. But, from my personal experience I would clearly choose deck at 40 since you lack of draw power here, other that searchers and maxx c generate. I know that Plant Synchro does well with no draw power but this aint the same deck, it has some forced choices which could slow it down a bit.
2nd Attempt:
-2 E-con
-1 Reaper
This is enough, but we can go further:
+1 Dark Simorgh/Birdman
(-1 Bell) -> if you prefer this one for BLS and prefer to have more than 40 cards due to tengu and GK engine well then, keep bell but not more than 41 in your deck!Note that Bell is just for da lulz as you said yourself since watching hands won't make it any better.
Its hard to edit this deck and increase its consistency with those requirements it needs to fulfill but if I were to use it, I would do like that and test those changed to see which ones would be best.
