At the beginning of the season, I figure the priority for the Big 6 would be in this order:
1. EPL title
2. CL title
3. FA Cup
4. EL title
5. League Cup
This doesn't account for CL spots (i.e. top 4). As the top 2 trophies became less of a probability to us (or nonexistent when it comes to CL title), the EL became more of a priority, as it's still a Euro cup, plus it gave us an in to next season's CL. I'd argue the EL becomes more of a priority for teams looking for trophies (over the FA Cup), but less for those that want to guarantee a top 4 spot, hence why you see Spurs not 'go for it' recently. I'd think any Top 6 team in the EL for the foreseeable future will have to deal with the tension of whether or not to spend precious resources on an EL run. If a top 4 spot isn't nailed on by February, it will be interesting to see how a top 6 team will allot their resources.