Does a high concentration thc plant require more work then a lower one or does it depend on the plant?
It's a variety of things. Genetics will determine potency potential, but correct lighting and nutrients help a lot.
How hard a plant is to grow has little to do with the THC in it. In fact I'm grown awesom plants from swag bag seeds and had crap plants from dank bag seeds. But my system does better with plants that I can keep 1' in veg state and get to be about 3' when in bloom. Short bushy plants just don't do well. So pick a plant that grows well in your system or be willing to change your system to your plants. Some strains take longer to rippen, like cough. But that doesn't mean they are harder to grow just longer to grow (but well worth it). Try not to mix alot of kinds in one grow system. I've wanted to try to vinning Mary Jane plants.
HI, well I have always been taught that an Indica dominant plant seem to have an ease of growth fairly easy compared to a Sativa dominant plant. Sativas tend to be more picky when it comes to giving them what they need as most indicas will thrive in more worse conditions. I would say start w/ an indica dominant strain for you first grow... good luck and Peace be the Journey!!