NA is always going to cost more in terms of HP/$. You could do a simple turbo kit on the B16 and make 200whp on LOW boost and have a fun car. But the weak link on the B16 is the pistons, they don like much more than 250ishwhp

B20VTEC is cool, itll be fun, but you have a HEAVY chassis. EM1s are NOT LIGHT and im sorry for a car to be FUN and only have 200whp NA , it has to be in like a EG Hatch, CRX or EK Hatch. SIs are heavy with the power windows, ac, PS, etc etc etc.

200whp B20vtec will be about 70whp over a STOCK B16, which is A LOT but its still a 14 second car at best.

IMO If you are really wanting to stay NA, i would sell your B16 longblock for like $800-900, pick up a ITR longblock ( i happen to have one for sale) and a header. Make 190-195 and its OEM reliable.

B20 VTEC, you are going to have a lot more on your plate. Youll need to do Pistons (Aftermarket or RS Machines), ITR cams at the minimum, ARP rod bolts if you stick with stock rods (to be able to really rev it with no problems), then you got the LSVTEC conversion, its a lot more labor intensive.

something to think about. Best thing would be to tell us your REALISTIC BUDGET