Equivalent is bad. Equivalent means the fight's not certain, and could be catastrophic based on the values of the three variables being used to equate your fleets. Mouse over the word "Equivalent" and you'll see the breakdown - if they have superior numbers, that beats superior tech most of the time. Fleet cap doesn't mean that much because you (or they) can exceed the cap when as needed; you'll pay more maintenance but it can be handy for cracking a particularly defended system early game. Especially if you know you're going to lose ships in an upcoming assault, feel free to build past the cap.
Mind that you CAN beat a fleet that has higher fleet strength than yours does, but only if you've got some concrete advantage - like tons of point defense against a fleet that's packing only missiles. Or they've got a fleet of large-weapon cruisers versus you with tons of high-evasion corvettes.
In general, early-game warfare is best fought on the defensive: Starbases are overwhelmingly powerful for their cost, and won't be irrelevant until at least cruisers are in play. Plop a defensive platform next to one for the FTL snare and enemies are unable to bypass the base, effectively protecting everything else in the system. If you have to, you can often lure an enemy to such a system using a small fleet (or lone corvette) invading their territory then retreating while none of your other ships are in their territory.
If you're up for mods, try Fox's Sensor Mod. It doubles sensor ranges at all levels, making scouting bases worthwhile for keeping an eye on rival and neutral systems. If you're not, keep in mind that enemy AIs don't usually focus on science or construction ships. They're not that cheap but so long as you're at war or borders are open, you can send them in to look around. You don't have to assign a researcher to the science vessels for this, and probably shouldn't, as these ships are only there to scout and should probably be decommissioned afterwards.