Training Advice for this Winter and Early Spring

I've just completed my first Triathlon season. I'm pretty happy with my progress so far. 1 year ago, I was pretty much not exercising at with the exception of an occasional jog. Maybe 2 or 3 times a month. I decided to do a Sprint Triathlon, but I could not swim. At all. Friends laughing at me bad. So last winter the traing plan was pretty simple. Swim, Swim, Swim some more, Take swiming lessons, read swimming books. Swim Swim Swim. Now I swim right at 2:00min per 100 and I held that pace for 1500 at Tri-Indy. I ended up doing 2 sprints, 1 olympic, and a 15K road race this season. The swim is still my weakest event, but not by much. Next year I want to do 2 oly's, 2 or 3 sprints, a mini-marathon, and possibly a HIM (I'm eyeing the Muncie Endurathon). So my question is what do I do this Winter. I want to improve in all the events, but I'm not really sure how to structure my training. Back when I used to run Cross-Country and Track, The offseason was used for Base building, and I basically just did long easy runs or temp-runs everyday with 1 or 2 days rest each week. Should I implement the same type of strategy across all three sports focusing on increasing enduance in each? The other idea I have is to do a series of 6-10 week "camps" where I focus on 1 sport at a time. Running and Cycling "camp" would focus on building endurance by doing lots of miles, and long interval work. The swim camp would focus on improving technique and endurance. I'd do a "camp" in each sport, which would get me to March, at that point I'd start a focused running plan to do a late May mini-marathon. then start incorporating more interval work through the race season to build speed and race readiness.
The other idea I had was to just follow the performance plans for HIM I found in a book I bought, "12 week triathlete." 10 weeks gets me to Christmas, take a break, follow 12 week plan again gets me to end of march, then I'll only be 6 weeks from my first road race of the season (Mini-marathon)
SO I guess that's a really long way of asking "Should winter training focus on 1 sport at a time, or should I just continue with the Multi-sport plans?
Yea I know, the obvious answer is to get a coach. I'm just not sure I wanna go there yet.