Help me choose a new theme for my site

This task feels like it ought to be a lot easier than it actually is.

I have a site, mainly used for blog type posts of news items relevant to the focus of the site. There are a small number of static pages & I would like to increase these, although they will never be the main focus of the site.

So that you know what I’m talking about, the site is at https://www.elginism.com/

There are a number of reasons for updating the theme.

The original theme was based on a re-skinned version of the Ocadia theme, which was fairly popular at that time. I modified it a bit to make it fully XHTML compliant & tweaked various other parts of it to add items to the sidebar etc (this was in the era of WordPress pre-widgets). A few months later I did another update to it, to incorporate some features from a later revision of the theme, but in terms of keeping it up to date, that has been about it – most of what visitors to my site now see is a nearly 10 year old theme.

The site also has parallel social media accounts on Facebook, Twitter, Pinterest, Flickr etc, and I would like these to become more prominent – at the time the site was first set up, social media barely existed in the form that it takes today.

The other thing I would like to do, if find a way to make the existing massive corpus of posts more accessible to readers – there is a huge amount of information there, but a lot of it is hidden away & reverting to a google site search is ofen the fastest way of finding it still.

Anyway – at the end of the day, as part of updating the site, I would definitely like to update it with a new theme – one that would work better across a range of viewing resolutions, from smart phone to desktop. I’m not concerned about maintaining the current look, although I would splice elements of it into any new theme that I used, in order to maintain some sort of continuity.

In terms of the type of theme, I would like it to be three – when I started out with WordPress, it seemed that almost all themes were free, although this does not appear to be the case any longer – when I say free, I mean that the whole theme is free – I’m not desperate in getting a lite version of a theme, with constant reminders of the extra features in the premium version etc.

One thing I am considering is the stock 2015 theme that comes with the latest WordPress – I’ve never bothered using one of the default themes before, but it seems that if it allows enough customisation, it should be possible to achieve the sort of thing I am wanting to do with this. One concern I have here though, is that once the next stock WordPress theme comes along, that the current one will no longer be updated, other than for security fixes – I have no idea whether this is the case or not, but having a name that is a year means that it has the potential to rapidly seem out of date.

To be honest, I’ve looked at lots of options so far, but none really seems to stand out to me.

any suggestions would be welcomed.