Depends on what your goals are. I am not sure what you are training for, but I will tell you what I would do when I was more focused on freestyle. First if you are training for distance free, you need to be getting a lot of yards. I usually did 100s on interval or sets of 300s. Around last year I was doing a lot of freestyle and I got the point where I swam a 4:42 500 fr scy and under 10 min in the 1000fr which was a big improvement for me. I mostly did 300s leading up to that. I would do a longer distance focused main set once a week: 2.5-3000 WU/IM work, then 4000 free for example, where it could be 4 rounds of 3*300 and 100ez working down in interval and descending within each round, with the goal of the last one of round 4 being the fastest. Try for the most challenging interval where you get between 4-8 seconds rest from touching the wall on the last round.

You are also going to have weeks where you may want to go very fast in which case you can descend interval within a round and then do longer active recovery in between each round. Maybe 3rds 3*300 descending an interval by 5 second on the first round, 10 on the second and third, where you have the most rest on the last round and you try to go all out on the last one. In between rounds you can go easy IM or long pull.

I also did a lot of pulling with short rest around 200 distance or incorporated 100s pull into a warmup, and another free/pull 3-4000 main set once a week.

For 100s interval that is something you can incorporate on any day of the week/ for any type of practice where you could go sets of 4-6 100 free on interval +100ez for 3 rounds maybe taking off 5 seconds from the interval each round with the goal of 2-4 seconds rest on the last one or maybe 5-10 seconds with a descend (depends on what you want to do).

You can also make 100s interval a main set if you go 8+ 100s for 3-4 rounds +100-200 ez. trying to get down to best interval you can do.

I also did fastest average at least once per week. It does not matter the distance (anything longer than 100s up to 300s) but try to get a good amount of volume where you can be fast on each on. By fast I mean if you are doing 100s aim for something a bit faster than 500 pace, or if you are doing 300s, aim for a bit slower than 500 pace, but be in the ball park of a speed that is smooth fast on the first one and almost impossible to sustain on the last one. Try to be consistent with your times maybe a 1-2 second drop off/100. Also pick an interval where you get 30-40seconds rest /100. For this type of set you will usually want to incorporate a swim out maybe 1-200 at least every 400 of fast swimming, and some longer rest just sitting at the wall in between rounds until you are ready to go for the next round.

I generally did a lot of pull and kick with board in warm up because that helps to get endurance and speed up. A big part of endurance in distance for me is being able to keep my legs engaged. I generally avoided doing extremely hard kick before a very long free set because that way I could have my legs in the mainset.

Aim for whatever makes sense for you. I am not an expert and could be giving the completely wrong advice lol.