Here's a character model I decided to build just because I wanted one. I especially don't see any issue since a techmarine doesn't take up an HQ slot, you are allowed to purchase for for every HQ you purchase (barring command squads) so he's easy to include as long as points are available. He also has access to special issue wargear which is very interesting. There's also no option for artificer armour in special issue wargear so barring 3 special characters he is the only other 2+ save and is the only one who can be customized. He does only have 1 wound, but considering he's on a bike (in my army at least) that's T5/2+, he could be better equiped to withstand being rapid fired to death.
To build him, I took a torso from the standard rhino vehicle sprue, and used standard biker legs, along with the techmarine helmet from the ravenwing sprue and a couple shoulder pads with mechanicum icons. This was all pretty standard and still has me contemplating adding some more "techno-bling" to his armour - maybe with some thin plastic card. Opinions? His armour does look pretty basic.
|view from left, some decent mechanicum icons, but armour is very flat|
|plastic servo-arm goodness|
|view from right side|