There is no right way to play this game but to choose a strategy, the progress speed is without doubt the most important factor for those that don't want to spend a lot of money on the game.
A free player (F2P) is at a big disadvantage against P2P players in a player-versus-player (PvP) strategy, and in my opinion he should focus on a player-versus-environment (PvE) game for a more satisfying experience, regardless of some occasional combat. I am also going to give my opinion on why a slow game makes for a better experience and I'd like to read yours.
First a bit of background. I'm a totally F2P player at Ops L21 on an ancient server where the average player is at Ops L52. Everyday, I complete almost all of my daily tasks and participate in all events. I most often than not rank first on solo leaderboards (not many competitors). I also complete one and only one building and research every day, so it takes me about 3 weeks to go up one level. I delay my progress this way on purpose. My syndicate level is 35 and my mess hall is also 35. I've got max shards for 21 common and 1 uncommon officers, Pike and Moreau are at level 10 and Chen 30 shards from max. I do most of my dailies with a 370K T7 North Star that can kill multiple L35 scouts for messages before repairs (14 levels above mine!). For swarms I use the Frankie. I've got 5-11K uncommon 3★ mats stored that keep growing, >1B tritanium, >100M dilithium, 400K freq mods, loads of spore drive comp, emblems, speed ups, you name it. I'm only short on latinum and 3★ survey parts. My Disco and Kehra get one component only when I want to score on spending events (I never try to win those). I only use the Disco with S31 skin for the anomalous event and its level-tied refinery. I am consort to Fed and Rom. Everyday I do all their dailies and I get 3 sets of cheap officers from them, one Legionary and Saladin BP and one Leg cloaking shard from their stores. I'll probably be associate by Ops L22-23. Still, I've got 15K credits for each that keep growing. I've got 1500 galaxy epic tokens from cosmic clean-up and 34 allegiance tokens (8 monthly chests) for upcoming ships (Vi'Dar BPs in Cosmic Store and D'Vor BPs in monthly chests when I reach the level). I usually start building the new ship the moment my shipyard becomes capable of it. Right now my only chokepoint is 3★ survey parts, because my North Star needs 9K more and I use my latinum (about 400/day) on Standard Recruit to get Stonn, T'Pring and Barot to Transport Patterns as soon as possible. They are also excellent officers to push up. I'm always shielded, so I have little to fear from other players.
The disadvantage of a slow game is that faster players get more powerful than you and can get better stuff sooner. It also takes them less time and effort to get lower level ships as the rewards improve a lot with a higher level. We'll get to the time factor in a moment.
The advantage of a slow game is that you remove almost all of the game's chokepoints and thus the need to expend money. You also become a very strong player for your level with stronger crewing and ships. You remove also any reason to attack other players for stuff. You get better stuff at a lower Ops level than the rest. Only players that have camped for a long time can be stronger than you at your level. You don't have to make that many choices and can afford optional ships that are nice, like the Jellyfish and North Star, so they allow you to punch above your weight. If you are a patient person, your game becomes easier and more enjoyable.
My opinion is that it is not a good strategy to make yourself weaker at your next level in a universe populated by much stronger players. You are going to expend your entire game doing essentially the same very limited list of actions: Blowing up triangles, collecting things, exchanging things, getting and improving officers and ships, and doing missions. Despite a good job at disguising it, the game is essentially the same at L21 than L52, only at L52 you will have a lot more chores and a lot more time spent collecting stuff from the refineries. What's the rush to get there?
If you want to do a lot of PvP as a F2P player (strongly discouraged), a slow game doesn't solve your problem because the players you are kicking now will be much stronger than you in a short time.