[Striiker]

You may want to start on a class which tends to not be too gear dependent and which you can use to farm up some stuff to sell or use for your preferred melee class (like a warrior). This want, you're planning ahead. Later on, once you have leveled up the solo-capable class, you can twink a warrior or whatever you want.
I think that necros are the best solo class as they are quite self reliant. People all have opinions around which class is best. If you want a solo class which is also in demand later, then the Enchanter is a good choice.
I obviously have a bias towards enchanters as I play one as my main. It is a very challenging class to play well and you'll constantly be busy in groups when you get in one. You may have better luck getting grouped as an enchanter based upon your hours of availability. If I am up late, I often get invites to Howling Stones and Sebilis.
Necros are fun to play too. I've always liked the idea behind the necro. Many people play necros as a solo class. This has two effects. 1) Many players don't know how to effectively play a necro in groups (heals, mana transfers, darkness, etc) and 2) Many people don't see necros as having a lot of value in groups due to #1 and the fact that they rarely group with one. I happen to appreciate having a necro in my groups.