Upgrading my Giant Propel Adv Pro 2 2019 (parts)

So over the last fortnight, I’ve been on the hunt for a new bike. I was after a Cannondale System Six HI Mod but as you might be aware, the market in the UK is bare! The only way I could of got my hands on one would of been 2nd hand. I’ve been checking Eurobike this new and hoping that Annandale would be announcing a model next year but it was to no avail. Even a few other brands caught my eye who I generally wouldn’t of considered, well they was out of stock too so I gave up

So then I decided I’m going to keep my bike and settled for a 2nd hand mini Shimano Di2 9150 groupset on eBay (I currently have Shimano 105 mechanical). Shifters, front mech, rear mech and cables. Now the only downside to this situation is that my bike is rim brake so I have some exposed cables up via the head tube

Overall, I do actually love my bike, fits me well, fast and I actually love the colour. So my question is this, what else what you do/change?

Seeing as though the BB has to come out for the cables, I think my bottom bracket needs replacing anyway. I’ve had it since 2019 so is it worth going for a ceramic? I know ceramic lasts longer but will else will I gain?

Bar tape will be replaced, what’s quite a nice bar tape? Supercaz seems to have a good rep

Was thinking about getting a new chain, a KMC X11 SL

Bars, I test rode a Super Six and it had 400mm bars and it was so much better, I think mine are 420mm and they too wide having known what 400mm now feels like. Trouble is, I think I’m very limited because its Giant cockpit system

I look forward to any suggestions