I've been doing quite a few Slitherlinks recently (and puzzles containing Slitherlink elements, such as Area 51). I'm familiar with all the patterns described in the Wiki article but I feel like there's some stuff I'm still missing with them.
I'm currently stuck on this Area 51 puzzle and would like some tips on what the next step(s) are.
The rules of Area 51:
You are building a labyrinthian fence enclosing Area 51. The fence must separate the aliens, kept inside, from the cacti, which are outside. The finished fence must make an enclosed circuit without touching or crossing itself. A cell containing an uncircled digit must be surrounded by that many pieces of fence. Numbers inside dotted-circles must be inside the fence and show how many cells can be seen up, down, left, and right (plus itself) from that cell before reaching a fence. On darkened circles, the fence must have a 90 degree turn with straight sections before and after. On white circles, the fence must continue straight with a turn before and/or after the circle. Thanks to David Millar who created this puzzle variety.
Also, if you're aware of any more advanced strategies, please mention anything relevant - I'm not sure where I'm falling down here.
Here's my current board-state: