These are valid concerns, but I come to different conclusions.
Were NSR and BKS tied to each other because of being on the same block chain (in fact BKS not even existing, but only NSR), a shareholder who loses trust in one project needs to abaondon both projects at the same time because they are represented by the same token (NSR).
With BCE not being on a separate block chain you could have motions for the benefit of the stable currency part on the expense of the BCE part or vice versa. That can lead to situations as awkward as with two separate DACs.
With BKS being separate from NSR you can hold NSR while selling BKS and vice versa.
The 50k buy side liquidity phase comes after the phase in which the funds (which have been received in exchange for the auctioned NSR (BTC, PPC, LTC)) have been traded for NBT.
Whoever or whatever is processing this trade has a pocket full of BTC, PPC or LTC.
The current (buy side) liquidity is low because of the aftermath of the exchange defaults earlier this year. Lots of BTC (or other) that have been traded for NBT on those exchanges are not accessible or lost forever, while lots of those traded NBT are in the wild. That’s why the buy side has little liquidity. Or is this view incomplete or naive?
While this is worrying I think it’s not that drastic. The focus of the Nu development team shifts temporarily. The Nu code does what is expected from it. Major improvements or enhancements are not suffering from this shift of focus, because there are no major improvements planned, except for the NSR burning. In case of security related problems the development team is well-advised to fix them in the Nu code base, because they are likely to make trouble with the BCE code base 
Continuing the development of Nu costs money. The revenue of Nu is not yet very well - to say the least.
With BCE the chances for being able to pay for continuous development rise - be BCE in the same chain or not.
NSR need to be sold by Nu to pay for development of Nu (direct development or indirect development). I welcome to have that dilution for the creation of BCE!