Yeah exactly, I'll often save those yeast packs from the kits and pitch 2 together though, because they are usually not even enough to make the 4% beer the kit is for and I usually aim for 5-6% with my beers (or I use a single pack in a 10L ginger ale or cider. It's not bad yeast it's just often under pitched.
How long you boil for is completely up to you, I just did 20 minutes because it was the end of another brew day, I had everything set up already so I just disolved the syrup, threw some hops in, topped up with water and boiled and transferred. In this instance it added almost no time to my brew day and got me 10 more litres of beer in my keg.
Do you have a favorite, go to yeast or does it depend on beer style?