https://soundcloud.com/cris_camp/everlasting-1
 
another annoyingly happy tune....

Sounds like a summer song to get everyone on the feet in a club. mix comes across here OK.

Nice Philly synth-pop!   Sounds pretty good from here. 

I love this kind of music.  I'd write it, but I don't know how to get that insanely fat and punchy synth drum/bass sound.  Tips?  And what do you use to master?  REALLY well done!

very nicely done. Mix is perfect for the genre

 You guys liked it?  ..............................................................you have a weird taste in music.  Thanks ! :)
It came out a little too repetitive this time, sorry about that....
 I think the most important is to have a balanced and good sounding mix, at low speaker volume with nothing on the master.
Than.....
 On my master usually i have:
 - A regular EQ to cut the boxiness around 300-500Hz and boost and cut specific bands that is based on your song but usually boost the highs and the lows a bit like 1-2 db. 
- A saturation plugin like Camel Crusher to add some subtle saturation and it also has a compressor built in. I use the "British clean" or "subtle master" presets.
- A soft clipper like Gclip which i don't really tweak. This is to cut the spikes before the limiter so it won't distort.
- Than i have a limiter/maximizer like Boost 11  which you want to stay below 3db of crunching.
 Sometimes i also have a compressor to "glue" the mix together but i don't really think its useful.  I don't use a multi band compressor on my master because i try to make adjustments at individual track level.
  I mix as i go so i don't have to do much when the song is done. When I'm mixing I'm using my studio monitors otherwise i like to use my headphones to hear the fine details.
 

What synth(s) do you use for your drum and bass tracks? Any side chain compression with the kick drum and bass synth?

For drums i used samples played in a sampler (Grace). For toms i used TTS1 electric set. Not much processing on drums except the snare has some distortion and reverb and some filter automation.
The main bass is from Rapture LE "Fake Fanfare brass" where i changed some stuff like filter cut-off . Another higher layer of bass is Z3ta + preset C085. Another deeper layer of bass is from Synth1 a preset from Bigtone.zip called 21:BT oldschool lead. A  Pad from Rapture LE  "bed of partials". In the mid part there is a bass from U-he Zebralette "tas techno bass" preset.  For the lead sounds i used Neo Piano, Rapture Session and T-force Alpha Plus. Not all the layers plays together all the time. There is filter automation going on through the whole track.
All the bass track are ducked to the kick with side chain compression, in different amounts. For side chaining i used a ghost track but you can use the kick  track itself.  All the lead and bass tacks are EQ- ed so i cut some of the low end to leave room for the kick and the bass.
 So to get a fat bass sound probably you want to layer multiple sounds and EQ the low end just to leave room for the kick, but not too much. When you layer sounds you want to layer sounds of different frequency bands, like a lows, mids, upper mids, otherwise at low frequencies thy could interfere and sound bad...Also you want to use side chain compression from the kick drum to everything that can clash with the kick. Instead of side chaining sometimes i use Tal Filter 2.   You can't have loud kick or loud bass in a track and you have to choose from the beginning which one to dominate.
The best advice is to listen to some good music that you want to make and analyze it in details .  

I like this, it's uplifting. Some good dynamics in there with the breakdowns, and that kick drum really...kicks!

I think you have this genre mastered.  Ever tried symphonic music or jazz?