I'll +1 all the others regarding the shrimp, you'll find the guppies won't bother the larger shrimp (but will make a meal of any shrimplets).
The larger question of what you can stock in the tank is related to what and how much filtration you are using, and, more importantly, how attentive you'll be able to be with the tank.
Right now my 29 gallon is host to 50 (yes - fifty) fish, but it's 1) well planted with both stem, floating and carpet plants; 2) the tank has PLENTY of filtration: A Fluval 306 canister filter crammed with Seachem matrix, pot scrubbers and Fluval bio rings; and 3) I tend the tank daily - checking chemistry, pruning/removing dead plant matter, watching for odd behavior in the fish (all juvenile tetras except for six corys and 4 otos).
Water changes are bi-weekly and the filter gets a cleaning every six to eight weeks.
If you are starting out, the inch per gallon rule, while not great, is likely safe enough with the fish you describe - but with care and understanding and attention you can have a very nice, vibrant tank in 10 gallons (until the addiction kicks in and then there's no hope
You are off to a great start - this forum is a fantastic place to get help and learn everything from the basics to the advanced stuff!