I'm not a fan.
I've used it before and to get all the bells & whistles out of it is not fun. To get a site up using a standard template is easy; to get it looking anything like the websites you see featured in the Themes listing is not. If you want that you're going to be paying for the upgrade extras and/or going on a painful journey of HTML/CSS discovery. I note the theme editor is turned off by default. Wise. I discovered that after installing my first choice theme, and entering the site title... which exceeded the one-line character length that centred everything nicely (and it wasn't a long site name!), and it wrapped over onto the menu and blogging area. Beautiful. So I thought, very first thing, and here we go, time to get my hands dirty - and the theme editor was switched off. Which was actually a relief. I knew hours could be ahead of me to get everything as I wanted, and it wasn't worth the time investment at the moment. Then I'd another thought, and checked out how it looked on my mobile phone, and it was a bigger mess. So I scrapped that theme and went for another. And then another.
Wordpress once held sway and I understand why WA employ it, but other website builders have advanced a lot in the last few years and you can have a fully customised, desktop and mobile usable site for a whole less pain than you can with Wordpress. The SEO and load time issues have been (largely) addressed and latest tests debunk that Wordpress is still the Usain Bolt of the website and blogging world. It may still win but that win is no longer by a sizeable margin or guaranteed, and it's back to a photo-finish. Five years ago I'd still be advising Wordpress, today no.
However, if you choose one of the templates and stick to what (very) basic modifications it allows, you'll have a site with a few clicks. If you have no web design or technical knowledge it's the safe choice. If you do, you can still request the access to fiddle (at your own peril).
And here's the thing: you can always tell a Wordpress theme/site. Always. They all look the same. All follow the same format. I know part of that is the requirements of modern technology and standardising a look that works across multiple devices... but it's always the same look and feel.
Maybe I'm making too much of that and it doesn't matter. I've looked at other niche websites marketing in the area I'm about to, and yup, they're all Wordpress: same header and two column layout with right menu bar... and so will I be. My problem is, over and above a header change, maybe a different background (if your theme even allows that), then how to make yourself recogniseable or feel different? Okay, content and new blog pics, but it's like modern housing estates, sure maybe the inside may be furnished differently, but from the outside they're all the same. That's a Wordpress site too, in my opinion, and why I elected for the first time this year not to go Wordpress on my off-WA site.
Anyway, I'm only about to start course three. Maybe in later courses, modifying Themes is covered or some other tricks (and it's a whole other topic not really in WA's remit and probably not even worth it if I can quell my desire to have "this moved a bit here, and that a bit bigger" inclinations) so we'll see.