A half acre pond isn't very large. With LMB, YP, BCP, CC and BG you've got a lot of possible future biomass for a pond of that size. Keeping this in mind, you may want to consider what each of these species is capable of doing in your pond.

The BG will reproduce in large numbers in your pond producing a lot of biomass. Hopefully the LMB, the adult BCP and adult YP you stocked will keep their numbers down and allow them to grow to good harvest size.

BCP often times have a hard time spawning in smaller ponds. They spawn in early spring, the pond will then cool down with a large cold front and the males will abandon the nest. This causes the eggs and fry to die. Smaller ponds are particularly susceptible to this because of how quickly they can heat and cool... This can be a good thing because BCP can quickly overpopulate a small pond. However, the rare spring where temperatures stay gradual, they will successfully spawn and you will get quite a large crop of YOY BCP.

The 40 LMB you put in your pond will be spawning by next spring. That is going to be a lot of mouths to feed. They will help thin out your BCP if they do reproduce but may not be able to keep up. BCP spawn before LMB and their young will hammer the LMB fry mercilessly. So LMB recruitment can be very tough in small ponds where BCP do reproduce. This means there will be few LMB surviving to adulthood to keep the numbers of other fish at acceptable levels.

The YP will reproduce fairly easily in your pond with the structure Bill Cody mentioned but again, their will be large numbers of young born and even more biomass.

If your CC do successfully reproduce you are looking at another large amount of biomass being born into your pond. However, without the correct spawning structure you shouldn't have to worry about this.

You have to keep in mind, that a half acre pond can only support so much biomass. With supplemental feeding and aeration you can increase this biomass but only to a point. You may want to consider not encouraging natural reproduction in your pond but rather rely on annual or semi annual stockings to maintain your fish. This way you can control the exact numbers of the different fish species in your pond. Otherwise you may pay the price in the future with large fish kills in the summer and winter and extremely low growth rates. Plus you will have to intensively cull fish through seining, angling or other methods to keep the fish populations in balance.

If you were going to add another predator to your pond, I would go with HSB. They will not reproduce in your pond, so you can closely control their numbers. They will help you control the possible over population of the BCP and YP in your pond as well and they can be fed pellets. Plus they are excellent fighters on the end of the line and good eating.