I don't really find anything wrong with this, its the super-turtle approach to things tho, as your shields are maxxed, your damage output plummets and if you want to spend that much longer to make sure you don't die, I guess that's a valid approach.
In Beta I noticed that PvE only really got challenging once the npcs start using fun BO abilities against you. Vs players, going turtle doesn't have the same benefits, getting ganged up on by 3+ playerchar ships tends to be dangerous, especially when they start beefing up their weapons skills, or various debuff/mezz stuff.
Well i'd just like to point out that Regenerative Shields in T1 combined with energy setting on defensive will make you near invincible against any number of npc ships firing at you.
At max power to shields setting, your shilds will regenerate so fast the enemies cannot keep up. I'm looking forward to seeing if T2 is balanced more against this very very simple tactic.
The problem with Regenerative Shields and a turtling approach is the 10% shield bleed-through rating on them. You can keep your shields up constantly, but torpedo impacts will chip away at your hull. Transphasic torpedoes, which have a higher shield penetration rating, could be very bad news.
Enemies also make use of more "fun" abilities in the higher levels, like Tachyon Beam (better against Regenerative Shields because the low total HP causes the shields to drain faster, and they don't regen during the drain) and Target Shields.
regen are basically the best tank shields (ok its a toss up between them and resilient) so of course against the low difficulty starting mobs they will be effective.
As stated they come with drawbacks, later high burst damage or shield targeting attacks will cause issues, but when there not going you have a solid defense as long as you have some hull repair ability.