Breeding them for amusement in a combination tank is fine.
BUT - there is always more to do if trying for success / $$ to supplement your tank hobby.
As a side note, usually people with plecos, Ancistrus are the most easily bred ones.
And they need totes or tanks for the various size groups of babies which pop out and you need to consider micro foods for them, usually you culture like Vinegar Eels micro worms, and baby Brine shrimp.
A solid idea Ancistrus is for Longfin Green Dragon Plecos, Albino Green Dragons, always seem to be a hit and often not available at the normal lfs. Greg Sage of Select Aquatics has some amazing long finnedhttp://www.selectaquatics.com/
Or Super Red Ancistrus. Always popular.
During summer you can also buy a group of fish and breed them out doors in Rubbermaid or similar tubs.
Summer tubbing from Rachel O'Leary on YouTube is full of great ideas including shrimp in tubs. 2019 and work back.
Great advice above about checking with the lfs about what fish customers are asking for and what the lfs might be willing to trade for yours if you had them.
Our lfs, is not interested in customers excess fish to buy or trade.
Something really popular, is good / easy sell - orange Dwarf Crayfish CAMBARELLUS PATZCUARENSIS aka CPO. The color you see are pretty much the color you get. Good ones don't need to grow up to get bright orange they should already be really orange.
For shrimp, trends are strong always for #1 Red and for Blue.
Bloody Mary Shrimp are gorgeous little jewels. Never raised them myself and not sure how many culls they have in their babies.
Better quality usually means less culls.
Look for articles about what the shrimp trends are / new shrimp coming out from breeders / shrimp which win awards.
Bloody Mary shrimp different than Fire red Shrimp
Bloody Mary has a red body with translucent shell allowing color to shine through. Shine like a Ruby / Jewel.
Best example I can think of
https://soshrimp.com/bloody-mary-shrimp/
Fire Red Deep dark red shell
https://soshrimp.com/painted-fire-red-shrimp/
Pinto shrimp many different groups and price points.
Wine red look amazing and I bet these aren't for sale locally
https://jtibee.com/epages/5d8d722b-...21-44f3-9edd-1dfde4add597/Products/WR-Package
Which you can sell them for a bit better price.
Tangerine Tiger shrimp easy and beautiful. Look for ones which are really Tangerine color and not yellow orange. Some have orange eyes!
I adore shrimp! Also recommend Shrimp only tank for breeding.
Easy to grow in a 20 tall / takes up the same amount of space as a 10G. lots of room for bunches of moss and plants DW and water. Water is your friend and helps keep the shrimp safer and give plenty of room to grow.