I have done both and thoroughly enjoyed instructing and charter for different reasons.
I began instructing with little experience but made up for this with enthusiasm and doing the best I could for each student. Despite the lack of hands on flying - I found that I gained experience through teaching and my stick and rudder skills actually improved. I worked best at smaller flying schools and flying clubs, where I was able to dedicate more time to each student pre and post flight. I got alot of satisfaction from sending a student solo and helping them overcome difficulties and obtaining a licence. Some are even working in G/A and a few are in airlines. They keep in touch and I'm still proud of their ongoing achievements.
I have left instructing for now, but would consider returning to it one day - to bring some experience back as a CFI, ATO or even get a little flying school started. I left with a S/E Grade 1 rating. I chose not to pursue Multi engine and IFR instructing as I had minimum experience in both areas - and so chose to move into a charter role to obtain it.
With some charter experience I had obtained during my instructing years, I went into a M/E charter job 13 months ago and have loved it. Yes it has its moments - living out of a bag for days at a time, early mornings, long days, challenging weather conditions at times, unforseen changes - like extra pax or gear turning up, pax running late, sitting around in remote communities for hours ... waiting. But the flying is fantastic! It is interesting - you meet interesting people, stay in different places and will see different landscapes, seeing parts of the country you never knew would be so picturesque.
If you dont have the passion for it, and are just doing it for the hours - dont instruct. Its unfair to students paying $$$ for their training, makes life difficult for other instructors who have to do remedial with the students you didn't have the time for and gives young/less experienced instructors a bad reputation - including amongst charter operators, many of whom now are not keen to employ ex instructors due to a lack of skill and airmanship shown by some who probablly didnt put much effort in, evident by the claim that they 'didn't get anything out of it'
Good luck with the choice and have fun doing whatever path you take!
Mo
