My other website www.theviewfromthenorth.org has been online since 2007. I don't know why I had a sudden desire to have a website, it just seemed like a good idea at the time. Since then, there have been a few iterations in the design as Photium (the hosting service I use, and highly recommend) have made improvements, but it's fundamentally the same.
What I've found - and bear with me in this analogy - is that a website is like a garden. You lay it out, and plan and arrange things. You plant seeds and it grows as you publicise it and word gets round. You must feed and nourish it by adding new content and refreshing older work (I reworked almost every image on the site in 2016). You trim and prune, removing older images and galleries that were not getting looked at. You may even move house and start again, as I did with this website when I moved from Zenfolio to Squarespace. OK so maybe not the best analogy in the world, but you get my drift! The important thing though, like anything else worth investing your time in, is to stick with it.
I've got a whole heap of benefits from my website. I'm not famous, and I'm in a tiny niche within a niche within a niche, but it's given me a name that goes before me to an extent. I meet people who have seen my work online or in exhibitions, but don't know me. As a direct result of contact made through the websites, I've made friends with people who have contacted me, sold prints, sold pictures for use in magazines and books, been commissioned to take photographs, sold my self published books, been asked to do talks, and doubtless other stuff I've forgotten about.
But one of the less tangible, and unforeseen benefits has been the credibility it gives. Having an online presence not only showcases your work, it says something else - that you are an expert in your field. This of course presumes that your online body of work is coherent and of a high standard - my recommendation would be to NOT have a gallery of sunsets, a gallery of airshow pictures, a gallery of landscapes and a gallery of cats on the same website - put them all on Flickr and just choose one genre to dedicate your website to, or maybe a few if they are closely linked (e.g. portraits and weddings, football and rugby, landscape and nature, etc).
This can be leveraged. An example of this would be gaining access to places, either with or without permission is one of the biggest challenges in my photography. As I've increasingly moved away from climbing over fences and through broken windows to see places, I've sought permission to see places. If via email, I will send a link to the website for the recipient to look at to show that I approach things in a sympathetic way and I'm interested in the place itself. It doesn't always work, of course, but then finding access to a sealed up site isn't always successful either.
I deliberately didn't use my name in the URL. I wanted to separate myself from my photography. I've never regretted that. I've now kind of turned it into a brand of sorts, although that wasn't the intention back in 2007 - I'd just seen too many terrible pictures online with a crap watermark stating "copyright Joe bloggs photography" across them.
On the subject of watermarks - above you will see my own. I think they look OK, but there again, I designed them and I have no background in design apart from a GCSE I did in 1990. But watermarks are a bit of a contentious subject - some are so intrusive as to ruin the image, some look good, and some people think they're a waste of time as they don't prevent image theft. My perspective is that I don't watermark to prevent image theft (if I was so concerned about it, I wouldn't put images on the web), rather, I put them there to show who took the photo and provide a link back to my website. In an age of one click sharing of images, this is far more important, in my eyes.
(Fun fact - theviewfromthenorth.com wasn't available so I went for .org not realising that it was meant for voluntary organisations. It was only later did I realise that the .com website was owned by the company of the same name - the one who made the Fred Dibnah TV documentary programs.)
Of course, I've had some right chancers contact me, as well as some very random requests - see below for a selection (contact details have been redacted!)