The 817ND has specific qualities, that being its size, weight and low power consumption for portable use. The internal battery only lasts so long, thus expect a few hours of use, I would say less than two per battery. This makes it ideal for short excursions or an outing to the park or somewhere. It is convenient to pack up and take on trips as well. Alternative battery sources like LiPO can be obtained that offer faster charging so switching out batteries can be an option.
Here's the thing, that radio is fun to operate and it is convenient for portable use, but without an antenna and propagation expect disappointment. I get a kick making voice contacts with that radio, but with its low power it really shines using CW or digital modes. Digital means bringing along another device or two. CW is great with only a key adding to the overall weight.
First and foremost, the antenna should not be an afterthought. I have used and still use a variety of antennas depending on how and where I am going to use that radio. From wires to verticals, to yagi antennas it just depends on the location. My usual favorites are a Buddipole and an Off Center Fed antenna. From time to time a vertical on my vehicle sees some use. I have even used that radio with a three element yagi and that was enjoyable. A compromised antenna is nobody's friend whether using five or 100 watts. Still, that is the tradeoff for portability.
If you aren't planning on venturing far from an AC or DC power source or a vehicle, I would recommend a different radio. While you can turn down the power on the other radio, they will require more power on receive and transmit. There are plenty of other bells and whistles you won't find with the 817ND, but again that's the tradeoff. Turn down a 100 watt radio to twenty watts and you'll may eliminate current on the feedline too. With the Buddipole and OCF antennas I use a 1:1 current balun at the antenna feed point. RF back into the radio ruins everything. Some snap on ferrite core beads on the coax may due the trick too. There are operators that have zero clue about that and curse the radio or antenna. The radio and antenna are part of a system.
I see the 817ND as a wonderful all mode HT. I have used it during the ARRL VHF contest in the Single Operator Portable category and rack up plenty of points. It makes it very easy to take along when camping, without taking up much space. I repurposed an old laptop bag to carry that radio, various accessories, and a Mini-Buddipole.
Finally, that is not my only HF radio. I am a right tool for the job type of person, but sometimes a multi band/mode radio fits whether it is a Yaesu 8x7 variant, or some other radio. If you're not planning on putting it into a back pack and riding a bicycle with it somewhere, or hiking up a hill then the 817 may not be the radio for you. There are so many conditions, it is difficult to say what will work to expectations for any operator.
For me, the 817 is not my primary radio. It is an alternative radio that allows me to enjoy some casual radio time and combine the hobby with other activities. It is not a serious radio, it is a fun radio. Thus, if you're trying to make contacts, it is the wrong radio. If you're happy that you made a contact, it is.